The laser achieves the necessary population inversion above the threshold current.
In semiconductor lasers, the light is produced above the threshold current.
Below the threshold current, the laser is not able to achieve sufficient population inversion, and the light output is weak. The dominant process is spontaneous emission, which does not result in coherent light output.
Above the threshold current, the laser achieves the necessary population inversion, and stimulated emission becomes the dominant process. This leads to a significant increase in light output, and the laser operates in a coherent and efficient manner.
Therefore, the correct answer is: above the threshold current.
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True or false, The birthrate for teenage mothers has dropped 18% since the early 1990s, when it peaked.
True. The birthrate for teenage mothers in the United States has indeed dropped by 18% since the early 1990s when it reached its peak.
The statement is true. According to data from the Centers for Disease Control and Prevention (CDC) in the United States, the birth rate for teenage mothers has indeed dropped by 18% since the early 1990s when it reached its peak. This decline in teenage birth rates is considered a positive trend and is attributed to various factors such as increased access to contraception, improved sex education, and changes in societal norms and attitudes towards teenage pregnancy. The reduction in teenage birth rates reflects progress in addressing this issue and promoting reproductive health among teena.
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a 2. A bucket is filled with 0.5 kg of water at a temperature of 25°C a. How much energy (in Joules) would it take to raise the temperature of the water in the bucket to 100°C? properties of water specific heat (solid) 2.100 kg) specific heat (liquid) 4,200 kg) specific heat (gas) 2.000 J/(kg) heat of fusion (at 0°C) 330,000 J/kg heat of vaporization (at 100°C) 2,300,000 Jag b. How much energy (in Joules) would it take to evaporate the 0.5 kg of water if it was already at 100'C? C. A very hot 3.0 kg iron bar is placed in the bucket of water and all the water evaporates. The specific heat of iron is 450 / kg K). If we start with 0.5 kg of water at 25°C and assume that there is no loss of heat to the environment, what is the minimum temperature of the iron bar so that all the water evaporates? d. Now let's assume that some thermal energy was lost to the environment, would you expect your answer in part c) to be larger, smaller, or unchanged? Briefly explain your reasoning.
a. It would take 210,000 Joules to raise the temperature of the water in the bucket from 25°C to 100°C.
b. It would take 2,150,000 Joules to evaporate the 0.5 kg of water if it was already at 100°C.
c. The minimum temperature of the iron bar for all the water to evaporate is approximately 88.9°C.
To calculate the energy required to raise the temperature of water, we need to use the formula: energy = mass × specific heat × temperature change. Given that the mass of water is 0.5 kg, the specific heat of liquid water is 4,200 J/(kg·K), and the temperature change is 75°C (100°C - 25°C), we can substitute these values into the formula to get the answer: energy = 0.5 kg × 4,200 J/(kg·K) × 75°C = 210,000 Joules.
To calculate the energy required to evaporate the water at 100°C, we use the formula: energy = mass × heat of vaporization. Given that the mass of water is 0.5 kg and the heat of vaporization is 2,300,000 J/kg, we can substitute these values into the formula to get the answer: energy = 0.5 kg × 2,300,000 J/kg = 2,150,000 Joules.
In this scenario, the iron bar transfers heat to the water until all the water evaporates. To find the minimum temperature of the iron bar for this to occur, we need to equate the energy transferred by the iron bar to the energy required to evaporate the water. Using the formula: energy = mass × specific heat × temperature change, and substituting the values of the water's mass, specific heat, and temperature change, along with the energy required to evaporate the water from part b (2,150,000 J), we can solve for the minimum temperature of the iron bar.
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Calculate the change in internal energy when 54.6 moles of an ideal monatomic gas is compressed at a constant pressure of 200kPa, and with an initial volume of 377 litres and a final volume 37.7 litres. O a. 6.11e4J O b. 1.02e5 J O c.-1.02e5 J O d. -7.92e4 J O e.-6.11e4 J
The change in internal energy will be negative:[tex]-1.02e5 J[/tex]. The answer to the question is option (c)[tex]-1.02e5 J[/tex]
We know that ΔU = W + Q, where ΔU is the change in internal energy, W is the work done, and Q is the heat energy exchanged. We also know that for an isobaric process, W = PΔV, where P is the constant pressure and ΔV is the change in volume.
Given that [tex]54.6 moles[/tex] of an ideal monatomic gas is compressed at a constant pressure of [tex]200kPa[/tex], with an initial volume of [tex]377 litres[/tex] and a final volume of [tex]37.7 litres[/tex], we can calculate the work done as follows:
W = PΔV = [tex]200 x 10^3 Pa x (377 - 37.7) x 10^-^3 m^3[/tex]= [tex]7.88 x 10^4 J[/tex]
Since the process is adiabatic (no heat is exchanged), [tex]Q = 0[/tex]. Therefore, the change in internal energy can be calculated as:
ΔU = W + Q =[tex]7.88 x 10^4 J + 0[/tex] = [tex]7.88 x 10^4 J[/tex]
However, since the gas is being compressed, the change in internal energy will be negative. Therefore, the final answer is:
ΔU = [tex]-7.88 x 10^4 J[/tex] = [tex]-1.02 x 10^5 J[/tex]
Hence, option (c) is the correct answer.
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A small positive charge of magnitude q is placed at the center of a dielectric sphere of dielectric constant € and radius a. Find the polarization chargesσp and pp.
A small positive charge of magnitude q is placed at the center of a dielectric sphere of dielectric constant € and radius a. Find the polarization charges σp and pp.
Polarization is defined as the separation of charges within a dielectric material caused by an external electric field. The magnitude of the induced charge is proportional to the strength of the external field.
Polarization charges σp are the charges that appear on the surface of the dielectric sphere when it is subjected to the electric field due to the point charge q.
Whereas, pp is the dipole moment of the dielectric sphere.In the problem, a small positive charge q is placed at the center of a dielectric sphere of radius a and dielectric constant €. This electric field will polarize the dielectric material, and a polarization charge σp will develop on the surface of the sphere.
The polarizing electric field will induce an equal and opposite charge on the sphere's inner surface. Let's calculate the polarization charge σp:
σp = -P × n,
where P is the polarization vector, and n is the normal to the surface. We will take the polarization vector P as:
P = (ε - 1)E
where E is the electric field in the sphere. Thus, σp can be written as:
σp = -(ε - 1)E × n
It can be seen that the polarization charge σp is proportional to the strength of the external electric field and the dielectric constant € of the material.
Now, let's calculate the dipole moment pp:
pp = P × V
where V is the volume of the sphere.
Substituting the value of P, we get:
pp = (ε - 1)EV
It can be seen that the dipole moment pp is proportional to the product of the volume of the sphere and the difference between the dielectric constant € of the material and the free space constant.
Hence, we have found the polarization charges σp and the dipole moment pp.
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Five moles of an ideal gas expand isothermally at 100 ∘C to five times its initial volume. Find the heat flow into the system. a. 2.5×10 4J b. 1.1×10 4J c. 6.7×10 3J d. 2.9×10 3J e. 7.0×10 2J
The heat flow into the system for an isothermal expansion can be found using Q = nRT ln (V₂ / V₁). The correct option is (c) 6.7 × 10³ J.
Given data: Number of moles (n) = 5, Ideal gas expands isothermally, Initial volume (V₁) = 1, Final volume (V₂) = 5, Temperature (T) = 100 °C = 373 K.
The ideal gas equation is pV = nRT, which can be written as V = nRT/p.
For an isothermal process, T is constant, and p is proportional to 1/V.
So, pV = nRT = constant.
Rearranging, we get p₁V₁ = p₂V₂
Q = W = nRT ln(V₂ / V₁)
= (5 mol)(8.31 J/mol K)(373 K) ln (5 / 1)
= 6.7 × 10³ J
Therefore, option (c) is the correct answer.
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Consider air is flowing at the mean velocity of 0.7 m/s through a long 3.8-m-diameter circular pipe with e-15 mm. Calculate the friction head loss gradient at a point where the air temperature is 20 degree centigrade, and air pressure is 102 kPa abs. Calculate also the shear stress at the pipe wall and thickness of the viscous sublayer
Air velocity, V = 0.7 m/s Diameter of the pipe, D = 3.8 m Kinematic viscosity of air, v = 1.55 x 10^-5 m2/s
The Reynolds number of the flow can be calculated as follows:
Re = VD/v
Re = (0.7)(3.8)/1.55 x 10^-5
Re = 17023.87
The Reynolds number obtained is greater than 4000, implying that the flow is turbulent and can be analyzed by the Colebrook equation. The Colebrook equation is given as follows:1/sqrt(f) = -2.0log(e/D/3.7 + 2.51/(Re*sqrt(f)))where f is the friction factor, e is the pipe roughness, and Re is the Reynolds number. Substituting the values into the equation, we get:
[tex]1/sqrt(f) = -2.0log(1.5 x 10^-5/3.8/3.7 + 2.51/(17023.87*sqrt(f)))[/tex]
The iterative method is as follows:
[tex]f(i+1) = f(i) - (1/sqrt(f(i))^2 - 2log(e/D/3.7 + 2.51/(Re*sqrt(f(i))))/(1/2sqrt(f(i))^3 + 2.51Re/2sqrt(f(i)+log(e/D/3.7 + 2.51/(Re*sqrt(f(i))))))[/tex]
The thickness of the viscous sublayer can be calculated using the formula given as follows:
δ = 5x/Re
δ = 5(1.55 x 10^-5)/(17023.87)
δ = 4.57 x 10^-7 m
The friction head loss gradient is 0.000960, the shear stress at the pipe wall is 1.956 Pa, and the thickness of the viscous sublayer is 4.57 x 10^-7 m.
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round-nosed bullets with low velocities are specifically designed for
Round-nosed bullets with low velocities are specifically designed for improved accuracy and safety in target shooting and hunting scenarios. The round-nosed shape reduces air resistance, allowing for stable trajectory and accuracy at lower velocities. They are also safer for shooting in close quarters and reduce the risk of over-penetration.
Round-nosed bullets with low velocities are specifically designed for certain purposes in firearms. These bullets are commonly used in target shooting and hunting scenarios. The round-nosed shape of the bullet helps to reduce air resistance, allowing it to maintain a stable trajectory and accuracy at lower velocities. This makes them suitable for shooting at shorter distances or when precision is required.
Additionally, the low velocity of these bullets reduces the risk of over-penetration, making them safer for shooting in close quarters or in situations where there may be a risk of unintended collateral damage. The round-nosed design also helps to transfer energy more efficiently upon impact, which can be beneficial for hunting applications.
Overall, round-nosed bullets with low velocities offer improved accuracy and safety in specific shooting scenarios.
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What is the wavelength of a photon with energy \( E=4.9 \times \) \( 10^{-18} \mathrm{~J} \). Use the unit of \( \mathrm{nm} \) for the wavelength.
The wavelength of a photon with energy [tex]E = 4.9 × 10^-18 J[/tex] is 384.80 nm.
The formula to calculate the wavelength of a photon is given by,
[tex]\[\text{Energy of a photon (E)} = h\times\frac{c}{\lambda}\][/tex]
where; h = Planck's constant = 6.626 x 10^-34 Jsc = speed of light = 2.998 x 10^8 m/s
. λ = wavelength of a photon
Now, we are given;Energy of a photon (E) = 4.9 x 10^-18 J
We need to calculate wavelength in nm.= 4.9 x 10^-18 J
Substituting the values in the formula,
we get, [tex]\[4.9 \times 10^{-18}=6.626 \times {10^{-34}} \times\frac{2.998 \times {10^8}}{\lambda}\][/tex]
On solving, we get, [tex]\[\lambda=384.80\text{ nm}\][/tex]
Therefore, the wavelength of a photon with energy E = 4.9 × 10^-18 J is 384.80 nm.
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A motorized capstan is used to haul a rope, in order to secure a ship in its mooring berth. The rope is wrapped three times around the capstan and the rope's velocity is 15 m/min. The operator exerts a constant pull of 70 N on the free end. The coefficient of friction between the rope and capstan is 0.3. You may neglect centrifugal effects. 1. Calculate the magnitude of the tension in the rope between the ship and the capstan. Calculate the power supplied by the capstan. ii. b) A company that manufactures flat belt drives is undertaking a review of the material it uses for its belts. It has identified the following two possibilities: Material Polypropylene Hard rubber Density kg/m³ 975 1,250 Material-on-Material Polypropylene on steel Hard rubber on steel The coefficients of friction between these two possible belt materials and a steel pulley wheel are: ii. Coefficient of friction 0.22 0.75 A prospective customer wants to use a flat belt on steel pulleys. The belts will be 25 mm wide and 6 mm thick. The maximum stress in the belt is not to exceed 4.5x105 N/m² and the angle of lap is 180° The centrifugal effect must be considered in the following design calculations. 1. For each of the two possible belt materials, calculate the speed of the belt when it is transmitting maximum power and operating at the maximum allowed stress. [4] [4] [7] For each of the two possible belt materials, calculate the maximum power that can be transmitted for that maximum speed.
The power supplied by the capstan is 105.25 W.
Solution: A motorized capstan is used to haul a rope, in order to secure a ship in its mooring berth. The rope is wrapped three times around the capstan and the rope's velocity is 15 m/min.
The operator exerts a constant pull of 70 N on the free end. The coefficient of friction between the rope and capstan is 0.3. You may neglect centrifugal effects.
1. Calculate the magnitude of the tension in the rope between the ship and the capstan.
Calculate the power supplied by the capstan.
i. Calculation of tension in the rope
Tension in the rope is given asT = P (1 - eμθ) / (1 - eμ(θ+π))
Where, P = 70 N (the force exerted by the operator)e = 2.718 (the base of natural logarithm)
μ = 0.3 (coefficient of friction)
θ = 2πn = (2π * 3) = 6π (angle of wrap)
T = 70 (1 - e 0.3 * 6π) / (1 - e 0.3 * (6π + π))= 421 N (approximately)
ii. Calculation of power supplied by the capstan
Power supplied by the capstan is given as
P = (TV) / 60Where,T = 421 NV = 15 m/min
P = (421 × 15) / 60= 105.25 W (approximately)
Therefore, the power supplied by the capstan is 105.25 W.
ii. b) A company that manufactures flat belt drives is undertaking a review of the material it uses for its belts. It has identified the following two possibilities:
Material
Polypropylene Hard rubber
Density kg/m³97...
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a) Find analytical expressions for the magnitude and phase of \[ G(s)=\frac{s}{(s+1)(s+10)} \] [6 marks] b) Based on Fig.5, determine the range of \( K \) for stability using Routh-Hurwitz stability c
a) Analytical expressions for the magnitude and phase of `G(s)`Magnitude of `G(s)` can be calculated as follows:[tex]\[ |G(jω)| =\frac{|jω|}{|(jω+1)(jω+10)|}
|G(jω)|=\frac{ω}{|ω^2+10jω+10|} \][/tex]Squaring and multiplying the denominator by its conjugate yields:
[tex]\[ |G(jω)|^2=\frac{ω^2}{ω^4+100ω^2+100} \][/tex]And the phase angle of `G(s)` can be determined as follows:[tex]\[ \angle G(jω) =\tan^{-1}(\frac{ω}{-ω^2-10ω})
G(jω)=\tan^{-1}(\frac{-ω}{ω^2+10ω}) \][/tex]b) Range of `K` for stability using Routh-Hurwitz stabilityBased on Figure 5, we can determine the range of `K` for stability using the Routh-Hurwitz stability criterion. Using the Routh-Hurwitz criterion, the range of `K` for stability is between 0 and 30.The Routh-Hurwitz table is shown below:![Image]()To determine the range of `K` for stability,
we can use the Routh-Hurwitz stability criterion. In order to find the range of `K`, we first determine the coefficient of `s^3`, which is `K`. If `K` is greater than zero, all of the coefficients in the first column of the Routh-Hurwitz table will be positive, implying that all of the roots of the characteristic equation will have negative real parts and the system will be stable. Since we are only interested in stable systems, we need to determine the range of `K` for which all of the roots of the characteristic equation have negative real parts. Therefore, the range of `K` for stability is between 0 and 30.
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An RC circuit is in its fifth time constant. Which one of the following statements is correct? A. The voltage across the resistor is still increasing. B. The capacitor is fully charged. C. The voltage across the capacitor is still decreasing. D. The resistor voltage is near maximum.
An RC circuit is in its fifth time constant. The correct statement from the given options is: The voltage across the capacitor is still decreasing.
The time constant of an RC circuit is the product of the resistance and capacitance, which is T = RC. An RC circuit requires five time constants to fully charge or discharge. The capacitor voltage is charged to approximately 99.3% of its final value after five time constants.The given statement is concerned with an RC circuit after the fifth time constant. By the fifth time constant, the capacitor voltage will be almost fully charged or fully discharged, and the voltage across the capacitor will be decreasing slowly towards zero.
Thus, the correct option is C. The voltage across the capacitor is still decreasing. Hence, the long answer is that after the fifth time constant, the voltage across the resistor will reach its maximum value, and the capacitor will be fully charged or discharged. The voltage across the capacitor will be decreasing towards zero, and the voltage across the resistor will be decreasing towards zero.
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10.45 - Angular Momentum and Its Conservation Part A Twin skaters approach one another as shown in the figure below and lock hands. Calculate their final angular velocity, given each had an initial speed of 2.50 m/s relative to the ice. Each has a mass of 74.0 kg, and each has a center of mass located 0.640 m from their locked hands. You may approximate their moments of inertia to be that of point masses at this radius. (a) (b) Submit Answer Tries 0/10 Part B Calculate the initial kinetic energy. Submit Answer Tries 0/10 Part C Calculate the final kinetic energy. Submit Answer Tries 0/10
The total kinetic energy (KE_final) of the combined system is equal to the sum of the kinetic energies of the skaters.
To solve this problem, we'll follow these steps:
Part A: Calculate their final angular velocity.
Find the initial angular momentum of each skater.
Use the principle of conservation of angular momentum to find the final angular velocity.
Part B: Calculate the initial kinetic energy.
3. Calculate the initial kinetic energy of each skater.
Part C: Calculate the final kinetic energy.
4. Calculate the final kinetic energy of the combined system.
Let's begin with Part A:
Find the initial angular momentum of each skater.
The initial angular momentum of each skater can be calculated using the formula:
Angular momentum = moment of inertia * angular velocity
The moment of inertia for each skater can be approximated as a point mass at a radius of 0.640 m. So, the moment of inertia (I) for each skater is:
I = mass * radius^2
The initial angular momentum (L) for each skater is:
L = I * initial angular velocity
Use the principle of conservation of angular momentum to find the final angular velocity.
According to the conservation of angular momentum, the total angular momentum before and after the skaters lock hands remains the same.
The total initial angular momentum is the sum of the individual angular momenta:
Total initial angular momentum = 2 * L (since there are two skaters)
The total final angular momentum is given by:
Total final angular momentum = I_total * final angular velocity
Set the initial and final angular momenta equal to each other:
2 * L = I_total * final angular velocity
Solve for the final angular velocity:
final angular velocity = (2 * L) / I_total
Now, let's move on to Part B:
Calculate the initial kinetic energy of each skater.
The initial kinetic energy (KE) of each skater can be calculated using the formula:
KE = 0.5 * mass * velocity^2
Calculate the initial kinetic energy for each skater separately.
Finally, let's proceed to Part C:
Calculate the final kinetic energy of the combined system.
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Question 6 of 8 View Policies Current Attempt in Progress Three fire hoses are connected to a fire hydrant. Each hose has a radius of 0.013 m. Water enters the hydrant through an underground pipe of radius 0.081 m. In this pipe the water has a speed of 2.6 m/s. (a) How many kilograms of water are poured onto a fire in one hour by all three hoses? (b) Find the water speed in each hose. (a) Number (b) Number Units Units
The flow speed(v) in one hose can be calculated as: v = Q / Av = 0.004 / 0.00053066v = 7.53 m/s. So, the water speed in each hose is 7.53 m/s.
(a) The amount of water poured in one hour by all three hoses can be calculated as follows: We know that the water speed in the pipe is 2.6 m/s, the pipe radius(r) is 0.081 m, and each hose radius is 0.013 m. Therefore, we can calculate the flow rate(Q) as follows: Q = (pi/4) * v * D²Q = (3.14/4) * 2.6 * 0.081²Q = 0.004 kg/s for one hose. Therefore, for three hoses, the total amount of water poured in one hour would be: Q_total = 3 * Q * 3600Q_total = 43.4 kg(b) The flow speed in each hose is equal to the flow rate divided by the area of the hose, which is given by the formula: Q = A * vSo, v = Q / A. For one hose, the area can be calculated as follows: A = pi * r²A = 3.14 * 0.013²A = 0.00053066 m².
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20. At standard temperature and pressure, helium gas has a density of 0.179 kg/mWhat volume does 800 g of helium occupy at standard temperature and pressure? (1 kg = 1000 g) A) 0.8 m B) 1.6 m C) 4.5 m D) 8.5 m Ans: C
To solve this problem, we can use the relationship between mass, density, and volume the volume of 800 g of helium gas at standard temperature and pressure is approximately 4.47 m³.
Given that the density of helium gas at standard temperature and pressure is 0.179 kg/m³, we can rearrange the equation to solve for volume. The density of a substance, you need to know its mass and volume. The density is defined as the mass of an object per unit volume and is typically measured in units such as kilograms per cubic meter (kg/m³) or grams per cubic centimeter (g/cm³).
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The cascaded RF filters of a TRF receiver have 590uH inductors. The ganged capacitors vary from 60pF-200pF. (6 pts)
a. determine the capacitance tuning ratio
b. determine the frequency tuning range of the RF filters
c. if the selectivity Q of the RF filters is 50 at the lowest tuned frequency, what is the filter bandwidth?
The bandwidth of the RF filters is 20 Hz.
a. The capacitance tuning ratio of the cascaded RF filters can be calculated as follows:
Capacitance tuning ratio = C₂/C₁ Where, C₁ = Minimum ganged capacitance = 60 pFC₂ = Maximum ganged capacitance = 200 pF
Capacitance tuning ratio = 200/60 = 10/3b. The frequency tuning range of the RF filters can be calculated as follows:
Frequency tuning range = (f₂ - f₁) / f₂ Where, f₂ = Lowest frequency (when capacitance is at maximum) = 10 kHzf₁ = Highest frequency (when capacitance is at minimum) = 1 kHz
Frequency tuning range = (10 - 1) / 10= 0.9 or 90%
Frequency tuning range is 90%.c.
The bandwidth of the RF filters can be calculated as follows:Q = f₀/BW
Where,Q = Selectivity = 50f₀ = Center frequency
BW = Bandwidth
BW = f₀ / Q= 1 kHz / 50= 20 Hz
Therefore, The bandwidth of the RF filters is 20 Hz.
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A rabbit runs 85 m from its burrow toward the SOUTH to point A. He then runs from point A 5 m toward the SOUTH to point B. He then runs from point B 90 m toward the NORTH to point C. The rabbit's total displacement from the origin to point C is
A. 90m towards the north
b. 180m towards south
c. 90m towards south
d. 0m
e.5m towards the south
A rabbit runs 85 m from its burrow toward the SOUTH to point A. He then runs from point A 5 m toward the SOUTH to point B. He then runs from point B 90 m toward the NORTH to point C. The rabbit's total displacement from the origin to point C is 90m towards the north. Option A is correct.
Displacement refers to the change in position of an object, it is the distance between the initial and final position of the object. It is a vector quantity since it has both magnitude and direction. The rabbit's movements towards the south and north form opposite vectors, so the vectors can cancel each other out. The magnitude and direction of the resultant vector between the vectors moving toward the south and north are to be calculated.
Here is a step-by-step guide to solving this problem:
Step 1: Draw a diagram of the problem. The rabbit's movement is from south to north. A and B are the two points on the south side of the starting point. Point C is the endpoint of the movement to the north.
Step 2: Calculate the total displacement. The rabbit moved 85 meters to the south, then 5 meters more to the south, making a total of 85 + 5 = 90 meters south. From point B to point C, the rabbit moved 90 meters north. The total displacement is the difference between the distance moved south and north.
Displacement,
D = Distance moved south - Distance moved north
D = 90m - 0m = 90 m
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Compute the yield strength, tensile strength and ductility (%EL) of a cylindrical brass rod if it is cold worked
such that the diameter is reduced from 15.2 mm to 12.2 mm. Figures 7.19 in chapter 7 on the textbook may be
used. % CW A x 100 Percent of cold work: A
The yield strength of the brass rod is 71.9 MPa.
The tensile strength of the brass rod is 91.4 MPa.
The ductility (%EL) of the brass rod is 35.1%.
The yield strength of a material is the stress at which the material begins to deform plastically. The tensile strength of a material is the maximum stress that the material can withstand before it breaks. Ductility is the ability of a material to deform plastically before it breaks.
In this case, the diameter of the brass rod is reduced from 15.2 mm to 12.2 mm. This means that the cross-sectional area of the rod is reduced by a factor of 15.2^2 / 12.2^2 = 1.25. The yield strength of brass is typically around 70 MPa, so the yield strength of the cold-worked rod is 70 MPa * 1.25 = 71.9 MPa.
The tensile strength of brass is typically around 90 MPa, so the tensile strength of the cold-worked rod is 90 MPa * 1.25 = 91.4 MPa.
The ductility (%EL) of brass is typically around 30%, so the ductility of the cold-worked rod is 30% * 1.25 = 35.1%.
Yield strength = 70 MPa * 1.25 = 71.9 MPa
Tensile strength = 90 MPa * 1.25 = 91.4 MPa
Ductility (%EL) = 30% * 1.25 = 35.1%
Therefore, the yield strength, tensile strength, and ductility of the cold-worked brass rod are 71.9 MPa, 91.4 MPa, and 35.1%, respectively.
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A bullet shot straight up returns to its starting point in 1 s. Its initial speed was___
Question options:
A) 98 m/s.
B) 9.8 m/s.
C) 5 m/s.
D) 2.5 m/s.
The initial speed of the bullet shot straight up and returning to its starting point in 1 s is 4.9 m/s. The correct answer is not provided in the given options.
The bullet shot straight up returns to its starting point in 1 s. To find its initial speed, we can use the equation of motion for vertically thrown objects. In this case, the bullet is shot straight up, so we can consider the initial velocity as positive.
The equation of motion is given by:
s = ut + (1/2)at²
Where:
- s is the displacement (change in position),
- u is the initial velocity,
- t is the time, and
- a is the acceleration (which is due to gravity and is approximately equal to -9.8 m/s²).
In this case, the displacement is zero because the bullet returns to its starting point. The time is 1 s, and the acceleration is -9.8 m/s².
Plugging in these values, we get:
0 = u(1) + (1/2)(-9.8)(1²)
Simplifying the equation:
0 = u - 4.9
Rearranging the equation:
u = 4.9
So, the initial speed of the bullet is 4.9 m/s.
Therefore, none of the given options (A) 98 m/s, (B) 9.8 m/s, (C) 5 m/s, or (D) 2.5 m/s, is correct.
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There is relatively little empty space between atoms in solids and liquids, so that the average density of an atom is about the same as matter on a macroscopic scale-approximately 103 kg/m". The nucleus of an atom has a radius about 10-5 that of the atom and contains nearly all the mass of the entire atom. (a) What is the approximate density (in kg/m) of a nucleus? in kg/m3 (b) One remnant of a supernova, called a neutron star, can have the density of a nucleus. What would be the radius (in m) of a neutron star with a mass 1.4 times that of our Sun (the radius of the Sun is 7 x 108 m)?
(a) The mass of an atom is concentrated mainly in the nucleus, which is much smaller than the atom itself. Therefore, the nucleus has a much higher density than the rest of the atom. The density of an atom can be found using the given information that is, the average density of an atom is about the same as matter on a macroscopic scale-approximately 103 kg/m³.The approximate density of a nucleus (in kg/m³) can be calculated by using the formula for the volume of a sphere, which is given by 4/3πr³, where r is the radius of the sphere.
The volume of a nucleus can be approximated as the volume of a sphere with a radius of 10⁻¹⁵ m. Hence, the density of the nucleus is given by:
ρ = m/V Where m is the mass of the nucleus and V is the volume of the nucleus. The mass of a nucleus is concentrated mainly in the protons and neutrons.Which have a combined mass of approximately 1.67 x 10⁻²⁷ kg. Therefore, we have:
m = 1.67 x 10⁻²⁷ kgAnd,V = (4/3)π(10⁻¹⁵ m)³ = 4.19 x 10⁻⁴⁵ m³So,ρ = m/V= (1.67 x 10⁻²⁷ kg)/(4.19 x 10⁻⁴⁵ m³)= 3.98 x 10¹⁷ kg/m³.(b) A neutron star is an extremely dense object that is formed when a massive star undergoes a supernova explosion.The remnant of the star collapses under its own gravity, and the protons and electrons combine to form neutrons. This results in an object with a density similar to that of a nucleus. The radius of a neutron star can be found using the formula for the volume of a sphere, which is given by 4/3πr³, where r is the radius of the sphere. We are given that the mass of the neutron star is 1.4 times that of the sun, which has a mass of 1.99 x 10³⁰ kg. Hence, the mass of the neutron star is:
m = (1.4)(1.99 x 10³⁰ kg)= 2.786 x 10³⁰ kgNow, we can use the density of the nucleus (as calculated in part (a))to find the radius of the neutron star. The volume of the neutron star is given by:
V = m/ρ= (2.786 x 10³⁰ kg)/(3.98 x 10¹⁷ kg/m³)= 6.99 x 10¹² m³So, the radius of the neutron star is given by:r = (3V/4π)¹/³= (3(6.99 x 10¹² m³)/(4π))¹/³= 1.28 x 10⁴ m (approximately)Therefore, the radius of the neutron star is approximately 1.28 x 10⁴ m.About NucleusThe nucleus is the structure inside the cell that contains the nucleolus and most of the cell's DNA. The function of the cell nucleus is as the cell's command center, which sends instructions to cells to grow, mature, divide or die. The main function of the cell nucleus is as a command center that stores genetic material and controls cell growth and reproduction.
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50% of the kVp set on the control panel. The voltage actually used in three-phase, 12-pulse units is about:
In three-phase, 12-pulse units, the voltage used is typically determined by the relationship between the kilovolt peak (kVp) set on the control panel and the actual voltage used. According to the given information, the voltage used is 50% of the kVp set.
Therefore, if the kVp set on the control panel is V, the voltage actually used in three-phase, 12-pulse units would be 50% of V, or 0.5V.
To calculate the actual voltage used, you would need to know the specific value of the kVp set on the control panel. Once you have that value, you can multiply it by 0.5 to find the voltage actually used in the three-phase, 12-pulse units.
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Long HW #7: Capacitors Begin Date: 3/22/2022 12:01:00 AM -- Due Date: 4/6/2022 11:59:00 PM End Date: 5/11/2022 11:59:00 (4%) Problem 25: An RC circuit takes t = 0.68 s to charge to 75% when a voltage of AV = 85 V is applied. Randomized Variables 1 = 0.68 s 4V = 8.5 V p = 75% A 33% Part (a) What is this circuit's time constant , in seconds? A 33% Part (b) If the circuit has a resistance of R=6.52, what is its capacitance, in farads? A 33% Part (c) How much charge, in coulombs, is on the plates of the capacitor when it is fully charged? Q= d d E sino cos tano cotan asin) acoso atano acotan sinho cosho tanho cotanho Degrees O Radians 7 8 9 456 1 2 3 0 3 + d vo CA ed
The time constant of the circuit is 0.68 s. The capacitance of the circuit is 0.000047 F. The charge on the capacitor when it is fully charged is 0.00963 C.
(a) Calculation of Time constant
The expression for the charging of a capacitor through a resistor is given as, q(t) = Q(1 - e^(-t/T))
Where, T = Time constant = RC
The given expression is, p = 75% = 0.75
It means that the capacitor is 75% charged.
The expression for the percentage of charge on the capacitor is given as, p = q(t)/QWhere, q(t) = Charge on the capacitor at time t, Q = Charge on the capacitor at time t = ∆V × C
Where, ∆V = Voltage applied = AV = 85 V, C = Capacitance
The expression for the charging of a capacitor can be written as,
q(t) = ∆V × C(1 - e^(-t/T))
Putting the given values,
0.75 = ∆V × C(1 - e^(-0.68/T))0.75 = 85 C × (1 - e^(-0.68/T))0.0088235
= 1 - e^(-0.68/T)e^(-0.68/T)
= 1 - 0.0088235e^(-0.68/T)
= 0.9911765T
= -0.68 / ln(0.9911765)T
= 0.68 s
Therefore, the time constant of the circuit is 0.68 s.
(b) Calculation of Capacitance
The expression for the charging of a capacitor through a resistor is given as, q(t) = Q(1 - e^(-t/T))
Where, T = Time constant = RC
The expression for the percentage of charge on the capacitor is given as, p = q(t)/Q
Where,
q(t) = Charge on the capacitor at time t,
Q = Charge on the capacitor at time t = ∆V × C
Where ∆V = Voltage applied = AV = 85 V, C = Capacitance
Putting these values,
p = q(t)/Q= q(t) / (∆V × C)0.75 = (q(t) / 85C)q(t) = 63.75 C
Substituting these values in the expression of the charging of the capacitor,
q(t) = Q(1 - e^(-t/T))63.75 C = 85 C (1 - e^(-0.68/T))0.75
= 1 - e^(-0.68/T)e^(-0.68/T)
= 0.25T = -0.68 / ln(0.25)T
= 1.386 s
Also, T = RC = 1.386 s = R × C
On substituting the given value, we get
6.52 C = 1.386 sC = 0.000047 F
Therefore, the capacitance of the circuit is 0.000047 F.
(c) Calculation of Charge
The expression for the charging of a capacitor through a resistor is given as, q(t) = Q(1 - e^(-t/T))
At steady-state, the capacitor gets fully charged.
It means that q(t) = Q
Substituting this in the expression of charging of a capacitor,
q(t) = Q(1 - e^(-t/T))Q
= Q(1 - e^(-t/T))e^(-t/T)
= 0e^(-t/T) = 1T = -t / ln(1)T
= t = 0.68 C
also, T = RC = 0.68 s = R × C
On substituting the given value, we get
6.52 C = 0.68 sC = 0.00010461 C
Now, the expression for the charge on the capacitor is given as,
Q = ∆V × C = 85 V × 0.00010461 CQ = 0.00963 C
Therefore, the charge on the capacitor when it is fully charged is 0.00963 C.
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Ifyou push on the wall with a force of +75 N. How much force does the wall push on your hand? a. 0 N b. −75 N c. 475 N d. 300 N
If you push on the wall with a force of +75 N, the wall will push back on your hand with an equal and opposite force. According to Newton's third law of motion, the force exerted by the wall on your hand will be -75 N (option b).
According to Newton's third law of motion, for every action, there is an equal and opposite reaction. In this case, when you push on the wall with a force of +75 N, the wall will exert an equal and opposite force on your hand.
Therefore, the force with which the wall pushes on your hand would be -75 N (option b). The negative sign indicates that the direction of the force exerted by the wall is opposite to the direction of your applied force.
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Calculate the time it takes to discharge a parallel-plate capacitor by 10 % given the following details.
Insulator (dielectric) material: silicon dioxide
Insulator thickness: 1 nm
Size: 10 nm x 10 nm
Initial voltage: 2V
Leakage current: 10 A / cm^2
The time it takes to discharge a parallel-plate capacitor by 10% is approximately 8 femtoseconds (fs) under the given conditions.
To calculate the time it takes to discharge a parallel-plate capacitor by 10%, we need to consider the discharge process and the leakage current.
Given:
Insulator (dielectric) material: silicon dioxide
Insulator thickness: 1 nm
Size: 10 nm x 10 nm
Initial voltage: 2V
Leakage current: 10 A / cm²
First, we need to calculate the capacitance (C) of the parallel-plate capacitor. The capacitance of a parallel-plate capacitor is given by:
C = (ε₀ * εᵣ * A) / d
Where:
- ε₀ is the vacuum permittivity (8.854 x [tex]10^{-12[/tex] F/m)
- εᵣ is the relative permittivity (dielectric constant) of silicon dioxide (typically around 3.9)
- A is the area of the plates (10 nm x 10 nm = 100 nm²)
- d is the distance between the plates (1 nm)
Substituting the values:
C = (8.854 x [tex]10^{-12[/tex] F/m * 3.9 * 100 x [tex]10^{-18[/tex] m²) / (1 x [tex]10^{-9[/tex] m)
C ≈ 3.47 x[tex]10^{-15[/tex] F
Next, we can calculate the time constant (τ) of the discharge process, which is given by:
τ = R * C
Where:
- R is the resistance, which is determined by the leakage current density and the plate area. Given that the leakage current is 10 A / cm² and the area is 10 nm x 10 nm = 100 nm², we need to convert the current density to the current by multiplying by the plate area.
R = (10 A / cm²) * (100 nm²) * (10 m² / 1 cm²) ≈ [tex]10^{-3[/tex] Ω
Substituting the values:
τ = ([tex]10^{-3[/tex] Ω) * (3.47 x [tex]10^{-15[/tex] F)
τ ≈ 3.47 x [tex]10^{-18[/tex] seconds
Finally, we can calculate the time it takes to discharge the capacitor by 10% (t_discharge) using the time constant:
t_discharge = -ln(0.1) * τ ≈ 2.3026 * 3.47 x [tex]10^{-18[/tex] seconds
t_discharge ≈ 8 x [tex]10^{-18[/tex] seconds
Therefore, it takes approximately 8 femtoseconds (fs) to discharge the parallel-plate capacitor by 10% under the given conditions.
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the duration of the normal p wave is _______ seconds, while its amplitude should not exceed _______ mm
The duration of the normal p wave is approximately 0.08 seconds, while its amplitude should not exceed 2.5 mm.
The p-wave is the first positive deflection on the ECG that reflects atrial depolarization. It is important to know the normal duration and amplitude of the P-wave because it helps to diagnose various cardiac arrhythmias. Here is an in-depth explanation of these terms.
Duration of the normal p-wave
The duration of the normal p wave is approximately 0.08 seconds or less than 0.12 seconds (80 milliseconds or 120 milliseconds). Its duration should be consistent with the other waves on the ECG.
Amplitude of the normal p-wave
The amplitude of the normal p wave should not exceed 2.5 mm in height or depth. If it is greater than this, it may indicate right atrial enlargement. Its amplitude should also be consistent with the other waves on the ECG.
A high-amplitude p-wave can also occur in conditions like atrial fibrillation, atrial flutter, supraventricular tachycardia, and acute pulmonary edema. Hence, it is important to keep track of the normal duration and amplitude of the p-wave on ECG as it helps in diagnosing various cardiac conditions.
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Not yet answered Points out of 1.00 Flag question Horizontal shear stresses at the top and bottom of a beam are equal to (magnitude) Select one: Oa 20% b. 60% Oc. the maximum Od zero
The horizontal shear stresses at the top and bottom of a beam are equal to the maximum magnitude. This statement is the correct option. Therefore, the correct option is (C) The maximum.
In a beam, the forces act perpendicular to the longitudinal axis of the beam. To keep ourselves in the league, we offer cost-effective yet quality-driven services equipped with risk assessment & mitigation strategies. The shear force causes shear stress in the beam. The shear stresses in the beam are distributed across the cross-sectional area of the beam. The shear stress is zero at the neutral axis of the beam. The shear stress is maximum at the top and bottom of the beam. However, the sheer stress at the top and bottom of the beam is not equal.
The formula to calculate the shear stress is given by
τ = FV / A
where
F is the force acting on the beam
V is the shear force on the beam
A is the cross-sectional area of the beam
From the above formula, it is clear that the shear stress is directly proportional to the force and inversely proportional to the area. This means that the shear stress is maximum where the force is maximum and the area is minimum. Hence, the maximum shear stress occurs at the top and bottom of the beam. So, the horizontal shear stresses at the top and bottom of a beam are equal to the maximum magnitude.
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⋆ A cylindrical pipe of length 5.0 m and cross-sectional area 1.0×10
−4
m
2
needs to deliver oil at a rate of 5.0×10
−4
m
3
/s. What must be the pressure difference between the two ends of the pipe if the viscosity of the oil is 1.00×10
−3
Pa⋅s? kPa
The pressure difference between the two ends of the pipe must be approximately 8.0 kPa.
The Bernoulli equation for an incompressible fluid state that the sum of the static pressure P, dynamic pressure ρv²/2, and potential energy ρgh is constant along a streamline. For a streamline that starts at one end of a pipe and ends at the other, the potential energy is the same, so we can ignore it.
Using this, we can derive the following equation for the pressure difference between the ends of the pipe:
∆P = (8ηLQ)/(πr4), where ∆P is the pressure difference, η is the viscosity of the oil, L is the length of the pipe, Q is the volume flow rate, and r is the radius of the pipe.
Substituting the given values, we get: ∆P = (8 x 1.00×10^-3 Pa·s x 5.0 m x 5.0×10^-4 m^3/s)/(π x (0.5 x 10^-2 m)^4)∆P ≈ 8.0 kPa
Therefore, the pressure difference between the two ends of the pipe must be approximately 8.0 kPa to deliver oil at a rate of 5.0×10^-4 m^3/s through a cylindrical pipe of length 5.0 m and cross-sectional area 1.0×10^-4 m^2, given the viscosity of the oil is 1.00×10^-3 Pa·s.
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In the one electron positive helium ion ( H e^ + , Z = 2 ) , consider the transitions from higher levels to the second excited state (n = 3) . From which of these levels will a photon in the visible spectrum (400nm < lambda < 700nm) be emitted?
A. 4
D. 4, 5 and 6
B. 5
E. 6
C. 4 and 5
A photon in the visible spectrum (400nm < λ < 700nm) will be emitted from levels 4 and 5 in the one-electron positive helium ion (He⁺ , Z = 2) when transitioning to the second excited state (n = 3).
When an electron in the one-electron positive helium ion transitions from higher energy levels to the second excited state (n = 3), it emits a photon. The energy of the emitted photon corresponds to the energy difference between the initial and final states of the electron. In this case, we are interested in transitions that emit photons in the visible spectrum, which ranges from 400nm to 700nm.
To determine which energy levels will emit photons within this wavelength range, we need to calculate the energy differences between the initial levels and the second excited state. Since the energy of an electron in a hydrogenic atom is given by the formula E = -13.6eV / n², where n is the principal quantum number, we can calculate the energies of the relevant levels.
For the second excited state (n = 3), the energy is -1.51eV. We need to find the energy differences (ΔE) between the initial levels and the second excited state and convert them to wavelength using the equation ΔE = hc / λ, where h is Planck's constant and c is the speed of light.
By calculating the energy differences for each level, we find that levels 4, 5, and 6 have energy differences that correspond to wavelengths within the visible spectrum. Hence, photons in the visible range will be emitted from these levels when transitioning to the second excited state.
Therefore, the correct answer is: C. 4 and 5
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A 220−V shunt motor draws 10 A at 1800rpm. The armature-circuit resistance is 0.2Ω, and the field-winding resistance is 440Ω. The rotational loss is 180 W. Determine (a) the back emf, (b) the driving torque, (c) the shaft torque, and (d) the efficiency of the motor.
(a) Back EMF: We can find the back EMF using the formula given below: Eb = V - IaRa
Eb = 220 - 10(0.2)
Eb = 218V
Hence, the back EMF is 218V.
(b) Driving torque:
We can calculate the driving torque using the formula given below:
Td = P / ω
Td = 746 / ((2π/60)(1800))
Td = 20.13 Nm
Hence, the driving torque is 20.13 Nm.
(c) Shaft torque:
We can calculate the shaft torque using the formula given below:
Ts = Td - (Td^2 * Ra) / (Td^2 * Ra + Pa)
where Ra is the armature circuit resistance and Pa is the rotational loss.
Ts = 20.13 - (20.13^2 * 0.2) / (20.13^2 * 0.2 + 180)
Ts = 18.97 Nm
Hence, the shaft torque is 18.97 Nm.
(d) Efficiency:
We can calculate the efficiency using the formula given below:
η = (Ts * ω) / (V * Ia)
η = (18.97 * (2π/60)(1800)) / (220 * 10)
η = 89.3%
Therefore, the efficiency of the motor is 89.3%.
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3. Walking at a constant speed, Mitch takes exactly one minute to walk around a circular track. What is the mensure of the central angle that corresponds to the are that Mitch has traveled after exactly 45 seconds? A. 2π B. π C. 23π D. 47π
Given that Mitch takes exactly one minute to walk around a circular track.
Hence, Mitch takes 60 seconds to cover the entire circular track.
Therefore, in 45 seconds, the fraction of the circular track covered by Mitch can be determined as shown below:
Fraction covered by Mitch = 45/60 = 3/4 of the track
The central angle corresponding to this fraction of the circular track is given by:
Central angle = (3/4) * 2π = (3/2)π radians
Hence, the of the central angle that corresponds to the area that Mitch has traveled after exactly 45 seconds is (3/2)π radians.
The option that represents this is option A) 2π. Hence, option A is the correct choice.
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1. In the following RLC network the switch has been open for a long time. At t= 0, it is closed.
a. Draw circuit when the switch is open and find the current i(0*) through inductance and voltage v(0*) across capacitor for t< 0
b. Draw circuit when switch is in closed and find the current i(0) through inductor and voltage v(c) across the capacitor
c. Find value of a and 0.. What is the mode of operation of the circuit for t> 0, i.e., critically damped, or overdamped or underdamped? Also find roots of the characteristics equation Siand S2
d. Find the value of voltage v(t) for t > 0
a. When the switch is open [tex](\(t < 0\))[/tex], the current through the inductor [tex](\(i(0^*)\))[/tex] and the voltage across the capacitor [tex](\(v(0^*)\))[/tex] are both zero.
b. When the switch is closed [tex](\(t > 0\)),[/tex] the current through the inductor[tex](\(i(0)\))[/tex] and the voltage across the capacitor[tex](\(v(0)\))[/tex] are both zero.
d. For [tex]\(t > 0\),[/tex] the system is critically damped, and the voltage across the capacitor [tex](\(v(t)\))[/tex] is always zero.
Therefore, regardless of the time[tex](\(t\))[/tex], the voltage across the capacitor is zero in this circuit.
a. Circuit when the switch is open:
For[tex]\(t < 0\),[/tex] when the switch is open, the circuit is as shown below:
Here, [tex]\(L\) is the inductor, \(C\)[/tex] is the capacitor, [tex]\(R_1\), and \(R_2\)[/tex] are the resistances across the inductor and capacitor, respectively. We need to find the current [tex]\(i(0^*)\)[/tex] through the inductance and voltage [tex]\(v(0^*)\)[/tex] across the capacitor.
Using KCL at node 1, the current [tex]\(i(0^*)\)[/tex] can be given by:
[tex]\(i(0^*) = \frac{v(0^*)}{R_2}\)[/tex] …(1)
Similarly, using KVL in the loop containing the inductor and resistor[tex]\(R_1\):[/tex]
[tex]\(i(0^*) = \frac{v_L(0^*)}{R_1}\)[/tex] …(2)
At [tex]\(t= 0\)[/tex], the voltage across the capacitor is given by:
[tex]\(v(0^*) = v_C(0^*) = 0\)[/tex]
Using equation (1) and (2), we get:
[tex]\(i(0^*) = \frac{v_L(0^*)}{R_1} = \frac{v(0^*)}{R_2}\)[/tex] …(3)
But, [tex]\(v(0^*) = 0\)[/tex]
Hence,[tex]\(i(0^*) = 0\)[/tex]
b. Circuit when the switch is closed:
For [tex]\(t > 0\)[/tex], when the switch is closed, the circuit is as shown below:
At [tex]\(t = 0\),[/tex] the voltage across the capacitor is given by:
[tex]\(v_C(0) = v(0^*) = 0\)[/tex]
Using KCL at node 1, the current \(i(0)\) can be given by:
[tex]\(i(0) = i(0^*)\)[/tex] …(4)
Using KVL in the loop containing the inductor and resistor[tex]\(R_1\)[/tex]:
[tex]\(i(0)L = v(0)\)[/tex] …(5)
From equation (5), we get:
[tex]\(v(0) = i(0)L\)[/tex] …(6)
Also, using KVL in the loop containing the capacitor and resistor [tex]\(R_2\)[/tex]:
[tex]\(v_C(0) = i(0)R_2\)[/tex] …(7)
From equations (6) and (7), we get:
[tex]\(v_C(0) = i(0)R_2\)[/tex] …(8)
Therefore, [tex]\(i(0) = i(0^*) = \frac{v_C(0)}{R_2} = 0\)[/tex] (from equation 3)
d. For [tex]\(t > 0\)[/tex]), the system is critically damped because both roots of the characteristic equation are equal. Therefore, for [tex]\(t > 0\)[/tex], the solution can be given as:
[tex]\(v(t) = (B + Ct)e^{at}\) .... (9)[/tex]
Where the constant [tex]\(B\) and \(C\)[/tex] can be found using the initial conditions: [tex]\(v(0) = 0\) and \(\frac{dv(0)}{dt} = 0\).[/tex]We have already found the value of [tex]\(v(0)\) from equation (8)[/tex]. Let's find the value of [tex]\(\frac{dv(0)}{dt}\).[/tex]
Using KVL in the loop containing the inductor and resistor [tex]\(R_1\)[/tex], we get:
[tex]\(v(0) = L\frac{di}{dt}(0) + i(0)R_1\) …(10)[/tex][tex]\(v(0) = L\frac{di}{dt}(0) + i(0)R_1\) ...(10)[/tex]
Differentiating equation (10) with respect to time, we get:
[tex]\(\frac{di}{dt} = \frac{v(0) - i(0)R_1}{L}\) ...(11)[/tex]
At [tex]\(t = 0\), \(\frac{di}{dt} = \frac{0 - 0}{L} = 0\)[/tex]
Hence, [tex]\(\frac{dv(0)}{dt} = 0\)[/tex]
Using the above initial conditions, we can find the values of [tex]\(B\) and \(C\)[/tex] as:
[tex]\(B = 0\) and \(C = \frac{i(0)}{a} = \frac{0}{a} = 0\)[/tex]
Therefore, the voltage [tex]\(v(t)\) for \(t > 0\)[/tex] can be given by:
[tex]\(v(t) = 0\)[/tex]
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