Answer:
A. I = 12/(10 + 20mH) = 0.545 A
B. Time constant = 20mH
C. I = 0.545 * (1 - e^(-10/20mH)) = 0.49 A
D. V = 12 - IR = 12 - (0.545 * 10) = 10.91 V
E. di/dt = 12/20mH = 0.6 A/s
F. It will take 3 time constants for the current to reach 99.4% of its maximum value.
Explanation:
If a 2.5 m long pendulum has a bob of 75 g. Calculate its Period, Frequency, and velocity at
equilibrium after its bob is pulled 10 cm above equlibrium and then released.
Time period and frequency of the pendulum are respectively 3.17 second and 0.315 second⁻¹. The velocity of its bob at the equilibrium is
140 cm/s.
Given parameters:
Length of the pendulum, L = 2.5 m = 250 cm.
Mass of the bob, m = 75 g
And, bob is pulled 10 cm above equilibrium and then released.
acceleration due to gravity, g = 9.8 m/s².
Hence, time period of the pendulum is, T = 2π√(l/g)
= 2π√( 250/980) second.
= 3.17 second.
Frequency of the pendulum , n = 1/T = 1/3.17 second⁻¹ = 0.315 second⁻¹.
Let v be the velocity of the bob at equilibrium,
Kinetic energy at equilibrium = potential energy at the highest point
⇒ 1/2 × 75 × v² = 75 × 980 × 10
⇒ v = √(2×980×10)
= 140 cm/s.
So, the velocity at equilibrium after its bob is pulled 10 cm above equilibrium and then released is 140 cm/s.
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How has the magnet affected the block of material next to it?
The magnet affected the block of material next to it because it exerts an attractive or repulsive force on other objects.
How do magnets affect other materials?Magnets do the retinue things: Attract certain materials, such as iron, nickel, cobalt, certain steels, and other alloys. apply an attractive or repulsive force on other magnets (opposite poles attract, like poles repel).
Magnetic forces are oblivious forces; they pull or push on objects without touching them. Magnets are only attracted to a few 'magnetic' metals and not all matter. Magnets are attracted to and repel other magnets.
So we can conclude that Materials with a magnetic field can attract other materials with such a field. Materials that are not magnets do not have a net outer magnetic field.
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If the average distance from Venus to the Sun is given to be 0.7AU, what is its period?
If the average distance from Venus to the Sun is given to be 0.7AU, its time period is 208.49 days.
Kepler's laws of planetary motion :
According to this law, the semi-major axes of the planets' orbits are directly proportional to the squares of the planets' orbital periods.
radius of the venus = 0.7AU
radius of the earth = 1 AU
orbital period of the earth = 365 days
According to the Kepler's 3rd law of planetary motion :
T² ∝ R³
T² = k R³
k = T²/ R³
[tex]k = \frac{T^2_v}{R^3_v} = \frac{T^2_e}{R^3_e}[/tex]
T² /(0.7)³ = (365)² /(1)³
T = [tex](0.7/1)^{\frac{3}{2}}[/tex] X 365
T = 208.49 days
If the average distance from Venus to the Sun is given to be 0.7AU, its time period is 208.49 days.
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Figure 1 shows a large wind farm of the coast of the UK.
The mean power outputs of the wind farm is 696 MW, which is enough power for 580,000 homes.
Calculate the mean power needed for 1 fame:
Give your answer in watts.
Based on the total power output by the wind farm, the mean electrical power for 1 home = 1200 W
What is the mean electrical power needed for 1 home?The mean electrical power needed for 1 home is determined as follows:
Mean power for 1 home = total power output by the farm / total number of homes
Based on the data provided:
The total number of homes that can be powered by the power produced from the wind farm is 580,000 homes
The total power output by the wind farm is 696 MW
Converting MW to watts by multiplying by 1000,000
696 MW = 696 * 1000000 W
696 MW = 696000000 W
Mean electrical power for 1 home = 696000000 / 580000
Mean electrical power for 1 home = 1200 W
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Answer:
1200 W
Explanation:
696 MW = 696,000,000 watts
1MW = 1,000,000 watts
696 MW = 580,000 homes
1 home = 696,000,000/580,000
1 home = 1200 W
a 4500 kilogram truck travels in a straight line at 10 ms what is its momentum
40,000 kg m/s will be the momentum if the truck at a truck mass of 4500kg and velocity of 10 m/s.
Given mass of a truck = 4000 kg
truck mass = 4 grams
velocity = 10 m/s
The formula of momentum will be:
p = mv
where, p = momentum
m = truck mass
v = velocity
substituting the values, we get:
momentum = 4000 × 10
momentum = 40000 kg m/s
Thus the momentum of the truck is 40,000 kg m/s
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Speculate on the different social dynamics behind lower - class drug use and middle -class drug use. For example , are there likely to be differences in motivation for use ? In the way individuals are introduced to drugs ? In the consequences for drug use ?
Social dynamics behind lower -class drug use is homelessness, criminal behaviors, association with gangs and unemployment whereas social dynamics behind middle -class drug use is peer relationships, extramarital relations and distortion of interpersonal family relationships.
What are the social dynamics behind drug use?Social factors that increase the risk for adolescent drug use can include popularity, bullying, peer relationships, and association with gangs.
Other possible factors can be social and familial influences. This can result in financial hardships due to job loss. It may also lead to certain behavior that can put family at risk and can also cause domestic violence within relationships.
Other social problems linked with SUDs can be housing instability, homelessness and unemployment.
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A 7.9 kg block initially at rest is pulled to the
right along a horizontal, frictionless surface
by a constant, horizontal force of 12.4 N.
Find the speed of the block after it has
moved 3.7 m.
Answer in units of m/s.
Answer:
[tex]v=3.4081\frac{m}{s}[/tex]
Explanation:
[tex]F=ma\\F=12.4N\\m=7.9kg\\a=\frac{12.4N}{7.9kg}\\a=1.5696\frac{m}{s^2}[/tex]
[tex]v^2=v_0^2+2a\Delta x\\v_0=0\frac{m}{s}\\a=1.5696\frac{m}{s^2}\\\Delta x=3.7m\\v^2=(0\frac{m}{s})^2+2(1.5696\frac{m}{s^2})(3.7m)\\v^2=11.6152\frac{m^2}{s^2}\\v=\sqrt(11.6152\frac{m^2}{s^2})\\v=3.4081\frac{m}{s}[/tex]
Buoyancy is a downward force exerted by a fluid on a body placed in the fluid.
OA. True
OB. False
Which of these has 28 protons and 26 electrons?
O Fe
O Fe2+
Ο Ni
O Ni2+
Answer:
here, if you have an iron which has 28 protons and 26 electrons, and we have to find the charge on the iron, the element and the symbol of the iron. So For 28 protons charge is 28 e. And for 26 electrons, charge will be -26 E. So total charges 28 E minus 26 E. Equal to two E. On I N S, plus two. No, we have to find the element. So atomic number is equal to Number of protons, which is 28, and this is atomic number four nickels. So the element is nickel and we have to find the symbol of iron. So the iron has to positive child. So the symbol will be and I took place So this completes the solution. Thank you.
Explanation:
A hot air balloon weighs 3100kg. The hot air in the balloon creates an upward force of 30,000N. What is the magnitude AND direction of the acceleration of the air balloon?
The magnitude and direction of the acceleration of the air balloon, with a mass of 3100 kg and a force of 30000 N acting on it is 9.68 m/s² upward.
What is acceleration?Acceleration can be defined as the rate of change of velocity.
To calculate the magnitude and direction of the acceleration, we use the formula below.
Formula:
a = F/m............. Equation 1Where:
F = Upward forcem = Mass of the balloona = Acceleration of the ballonFrom the question,
Given:
F = 30000 Nm = 3100 kgSubstitute these values into equation 1
a = 30000/3100a = 9.68 m/s² upward.Hence, the magnitude and the acceleration of the air balloon is 9.68 m/s² upward.
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____is formed either from water present in the atmosphere as snow, sleet, or from exposure of liquid____
to a temperature below___F.
Impact ice is formed either from water present in the atmosphere as snow, sleet, or from exposure of liquid water to a temperature below 32°F.
What is meant by impact ice ?Impact ice, a kind of induction icing, may form wherever that the temperature is close to or below zero degrees Celsius. Even on a fuel-injected engine, impact ice can clog the air filter and prevent the engine from getting the necessary air for combustion. As instructed by your POH/AFM, turn on alternative air or carburetor heat if you detect impact ice.Carburetor icing (ice that forms in the carburetor) happens when the venturi's decline in air pressure causes the moisture-filled air to cool quickly or as a result of gasoline evaporation.The ensuing ice buildup in the intake tube of the carburetor can significantly lower engine performance. In extreme circumstances, the intake flow might be so low that the engine can stall.Learn more about Liquid water refer to :
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6. How is research classified according to the following? a. Purpose b. Goal c. Levels of investigation d. Types of analysis e. Scope f. Choice of answers to problems g. Statistical content h. Time element
Answer:
I think the answer is the option h
hope this helps you
Must two bodies of equal momentum be moving in the same direction?
Yes, if two bodies have the same momentum, the velocities of the two objects needs to be equal to be moving in the same direction.
What is momentum?Momentum is the product of mass and velocity of a body in motion. It is a vector quantity.
Two bodies of equal momentum can only move in the same direction if their velocities are equal. This is because both the velocity and the momentum are vector quantities. Momentum is the product of mass, which is a scalar quantity and the velocity, which is a vector.
In conclusion, for two objects to have the same momentum and for their directions to be the same, they need to have the same velocity.
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Yes, two bodies of equal momentum must be moving in the same direction.
What is momentum?We know that momentum is the product of the mass and the velocity of the object, In fact, momentum is a vector quantity and it should be clearly stated here that the direction of the momentum vector have to be the direction of the velocity vector.
With this said, when we say that two object have the same momentum we are essentially saying that the velocity vector of the two bodies have to pointing in the same direction. Once the direction is not the same, the momentum of the objects can not ever be the same!
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A car moving with an initial velocity of 45 ms¹ is brought to a stop in 5 s. Find:
a) the deceleration of the car
b)the distance needed to stop the car
Answer:
a) -9 [tex]m/s^2[/tex]
b) 112.5 meters
Explanation:
Here is a formula for acceleration.
[tex]a=\frac{V_{f} -V_{o} }{t}[/tex]
We are given
[tex]V_o=45[/tex] m/s
[tex]V_f=0[/tex] m/s
[tex]t=5[/tex] s
Lets solve for [tex]a[/tex].
[tex]a=\frac{0-45}{5}[/tex]
[tex]a=\frac{-45}{5}[/tex]
[tex]a=-9[/tex] [tex]m/s^2[/tex]
Here is a formula for displacment.
[tex]x=V_o t+\frac{at^2}{2}[/tex]
[tex]V_o=45[/tex] m/s
[tex]t=5[/tex] s
[tex]a=-9[/tex] [tex]m/s^2[/tex]
Lets solve for [tex]x[/tex].
[tex]x=45*5+\frac{-9*5^2}{2}[/tex]
[tex]x=225+\frac{-9*25}{2}[/tex]
[tex]x=225+\frac{-225}{2}[/tex]
[tex]x=225+-112.5[/tex]
[tex]x=225-112.5[/tex]
[tex]x=112.5[/tex]
What two forces keep stars in equilibrium?
A. cosmic microwave background radiation
B. self gravity
C. thermal pressure
D. dark energy
According to the given information self gravity two forces keep stars in equilibrium.
The correct option is B.
What you mean by forces?The push or pull on a mass-containing item alters its velocity. An external force is an agent that has the power to alter the rest or flowing condition of a body. It has a direction and a magnitude. Like we discovered in a previous session, forces are significant because they create motion changes.
What is effect of force?An object can change its dimensions or shape, begin moving, stop moving, accelerate, or decelerate as a consequence of the a force acting on it. When two things contact, they exert pressures on each other that are identical in size but directed in the opposite direction.
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1. A child sits on a dock and notices that 8 wavelengths pass the end of the dock in 4 seconds. What is the
frequency of the waves passing the dock?.
2. What is the period of the waves in question 1?
Answer:
Explanation:
Given:
n = 8
t = 4 s
______
f - ?
T - ?
Frequency:
f = n /t = 8 / 4 = 2 Hz
Period:
T = 1 / f = 1 / 2 = 0.5 s
A dog sits 2.2 m from the center of a merry- go-round.
a) If the dog undergoes a 1.6 m/s2 cen- tripetal acceleration, what is the dog’s linear speed?
Answer in units of m/s.
second part
What is the angular speed of the merry-go- round?
Answer in units of rad/s.
The dog’s linear speed will be 1.88 m/s
The angular speed of the merry-go- round will be 0.85 rad/sec
centripetal acceleration = [tex]v^{2} / r[/tex]
given
r = 2.2 m
linear speed = ?
centripetal acceleration = 1.6 [tex]m/s^{2}[/tex]
centripetal acceleration C(a) = [tex]v^{2} / r[/tex]
linear speed = [tex]\sqrt{C(a) * r}[/tex]
= [tex]\sqrt{1.6 * 2.2 }[/tex] = [tex]\sqrt{3.52}[/tex] = 1.88 m/s
The dog’s linear speed will be 1.88 m/s
angular speed = linear speed / radius
= 1.88 / 2.2 = 0.85 rad/sec
The angular speed of the merry-go- round will be 0.85 rad/sec
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You stand in front of a mirror. How tall does the mirror have to be so that you can see yourself entirely?
a. same as your height
b. less than your full height but more than half your height
c. half your height
d. less than half your height
e. any size will do
If you stand in front of a flat mirror. The one-half of your height will be seen yourself entirely. Option C is the correct answer.
What is height?A person or anything can be measured from head to toe or from the bottom up by their height. In other words, a person's height indicates how tall they are. Distance units, such as meters, centimeters, millimeters, etc., are used to measure height. We may assess how much taller we get as we age. We frequently contrast the average heights of men and women in various nations.Take a look at your room's four walls. The height of a wall is measured from the ground to the ceiling. Remember how your class is organized in the school assembly, with the tiniest child in the front and the tallest youngster at the back.
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While cycling, the athlete can go up to a maximum of 30 km/h. If his/her acceleration is 9 m/s2, then calculate the time the athlete takes to reach the maximum speed.
The time the athlete takes to reach the maximum speed will be 0.93 seconds
acceleration = change in speed / time
initial speed = 0
final speed = 30 km / h = 8.33 m/s
acceleration = 9 [tex]m/s^{2}[/tex]
acceleration = change in speed / time
time = change in speed / acceleration = 8.33 / 9 = 0.93 seconds
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Question 3
During discussion, a student states, "The law of conservation of energy is not actually useful because no system is ever truly isolated from the rest of the universe. No system is truly closed. There will always be some amount of energy entering or leaving a system." You believe that energy conservation is a useful concept, and you want to
explain why. Which of the following responses is most true?
The most true response is: there are many situations in which difference between energy entering in a system and leaving a system is so small that we can ignore it - so some systems can be treated as if they are closed even they are not.
What is conservation of energy?Energy cannot be created or destroyed, according to the rule of conservation of energy. However, it is capable of change from one form to another. An isolated system's total energy is constant regardless of the types of energy present.
The law of energy conservation is adhered to by all energy forms. In a nutshell, the law of conservation of energy asserts that the system's total energy is conserved in closed systems, or systems that are separated from their environment.
In practical life no system is ever truly isolated from the rest of the universe. No system is truly closed. There will always be some amount of energy entering or leaving a system.
But there are many situations in which difference between energy entering in a system and leaving a system is so small that we can ignore it - so some systems can be treated as if they are closed even they are not.
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An athlete at the gym holds a 4. 0 kg steel ball in his hand. His arm is 70 cm long and has a mass of 4. 0 kg.
τ=Fd
In this instance, it will
τ=Fballdball+Farmdcenter of mass
τ = 4*9.81*.7 + 4*9.81*.35 = 41.2
and both of our forces have a magnitude of 4g*cos(55), but they are located in different places.
τ = 4g*cos(55)*(.35+.7) = 23.6
The term "magnitude" refers to an object's greatest size and direction. Scalar and vector quantities both use magnitude as a common factor.
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The speed of light in vacuum is 3*10^8m/s what it's speed in glass of refractive index1.5
Answer:
Speed of light in glass V = 2·10⁸ m/s
Explanation:
Given:
c = 3·10⁸ m/s - The speed of light in vacuum
n = 1.5 - Refractive index of glass
__________
V - ?
Speed of light in glass:
V = c / n
V = 3·10⁸ / 1.5 = 2·10⁸ m/s
If relativistic effects are to be less than 6%, then must be less than 1.06. At what relative velocity is = 1.06?
If relativistic effects are to be less than 6%, then must be less than 1.06. Hence, at a relative velocity (v) of 0.33c, gamma is = 1.06. This problem is solved using the Lorentz Factor.
What is the Lorentz Factor?The Lorentz factor is a correction parameter used to calculate relativity. Without this component, relativistic motion calculations simply fail, and we can obtain speeds that surpass the speed of light, which cannot be.
The calculation to the above solution is given as follows
Given:
γ = 1/ √1-(v²/c²)
It is logical to simplify by squaring both sides
⇒ γ² = 1/ 1-(v²/c²)
Taking the reciprocal of both sides, we have
1-(v²/c²) = 1/γ²
Transposing we have
v²/c² = 1 - 1/γ²
Since we are looking at v, lets us isolate it:
v = √[1 - (1/γ²) · c]
Inserting the Lorentz factor which is
γ = 1.06, we have
v = √[1 - (1/1.06²) · c]
Hence,
v = 0.33c
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Full Question:
If relativistic effects are to be less than 6% then gamma must be less than 1.06. At what relative velocity is gamma = 1.06?
You and a friend are astronauts. You push off eachother with a force of 100N. You both have a weight of 0 in space, but your mass is 110kg, and your friend’s is 80kg. Calculate the accelerations of both you and your friend
Since the force of gravity acting on a body in space is zero;
acceleration for the 110 kg person is 0.acceleration for the 80 kg person is 0.What is the relationship between the mass and acceleration of a body?The mass of a body is inversely related to the acceleration of the body if a constant force is applied to the body.
The greater the mass, the lesser the acceleration of the body.
Mathematically:
Force = mass * acceleration
The force acting on a body in space is zero.
Hence, acceleration = force / mass
For a mass of 110 kg;
acceleration = 0 / 110
Acceleration = 0
For a mass of 110 kg;
acceleration = 0 / 80
Acceleration = 0
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6. A constant net force acts on a magnitude of all of the following quantities pertaining to
the body EXCEPT
(A) Acceleration
(B) Kinetic Energy
(C) Momentum
(D) Speed
(E) Velocity
using references websites or maps and a different color line, draw the major crystal plates of the earth on your world map. label the names of the plates neatly
Answer:
The Earth's major plates are the African plate, the Antarctic plate, the Eurasian plate, the North American plate, the South American plate, and the Pacific plate.
Explanation:
A decibel meter reads a sound intensity of 80 dB when you stand 2 m from a loudspeaker. What will the meter read (in dB) if you stand 40 m away?
Answer:
Explanation:
L₁ =80 dB
S₁ = 2 m
S₂ = 40 m
__________
L₂ - ?
The intensity of the site is nearby:
ΔL = 10·lg(S₂/S₁)²
ΔL = 10·lg(40/2)² = 10·2·lg(20) = 20·1.3 = 26 dB
L₂ = L₁ - ΔL = 80 - 26 = 54 dB
Calculate the speed at the edge of a disc of radius 8.5 cm that rotates at the rate of 2.5 rev/s.
Answer in units of m/s.
The speed at the edge of a disc of radius 8.5 cm that rotates at the rate of 2.5 rev/s will be 21.25 m/s
Angular velocity is the rate of change of angular displacement
Mathematically it can also be calculated as linear speed divided by radius
linear speed = omega * radius
= 2.5 * 8.5
= 21.25 m/s
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a 2kg box with some initial velocity slides up a frictionless ramp which is at a 15-degree angle to the ground until the box comes to rest 1-sec later. Find the work done on the box.
Answer:
Approximately [tex](-6)\; {\rm J}[/tex], assuming that [tex]g = 9.81\; {\rm m \cdot s^{-2}}[/tex].
Explanation:
Let [tex]m[/tex] denote the mass of this box.
Decompose the weight [tex]m\, g[/tex] of the box into two components: perpendicular to the slope [tex](-m\, g)\, \cos(15^{\circ})[/tex] and parallel to the slope [tex](-m\, g)\, \sin(15^{\circ})[/tex]. The perpendicular component is balanced with the normal force of the slope on the box. In contrast, since there is no friction between the box and the slope, the parallel component isn't balanced and will be equal to the net force on the box:
[tex]F_{\text{net}} = (-m\, g) \sin(15^{\circ}})[/tex].
Note that [tex]F_{\text{net}}[/tex] is constant during this [tex]t = 1\; {\rm s}[/tex].
The acceleration [tex]a[/tex] of this box will be:
[tex]\begin{aligned}a &= \frac{F_{\text{net}}}{m}\\ &= \frac{(-m\, g) \sin(15^{\circ})}{m} \\ &= (-g)\, \sin(15^{\circ})\end{aligned}[/tex].
Let [tex]u[/tex] denote the initial velocity of this box. Since after the [tex]t = 1\; {\rm s}[/tex] of acceleration at [tex]a = (-g)\, \sin(15^{\circ}})[/tex] the velocity of the box is [tex]v = 0\; {\rm m\cdot s^{-1}}[/tex], the initial velocity of this box will be:
[tex]\begin{aligned} u &= v - a\, t \\ &= 0 - (-g)\, \sin(15^{\circ})\, t \\ &= g\, t\, \sin(15^{\circ}})\end{aligned}[/tex].
Initial kinetic energy of this box would be:
[tex]\begin{aligned} (\text{KE}) &= \frac{1}{2}\, m\, u^{2} \\ &= \frac{1}{2}\, m\, (g\, t\, \sin(15)^{\circ}})^{2}\end{aligned}[/tex].
The kinetic energy of this box is [tex]0[/tex] when the box is at rest. The change in kinetic energy was [tex](1/2)\, m\, (g\, t\, \sin(16^{\circ}))^{2}[/tex]. That energy change should be the opposite of the work the external force weight did on this box.
Substitute in [tex]m = 2\; {\rm kg}[/tex], [tex]g = 9.81\; {\rm m\cdot s^{-2}}[/tex], [tex]t = 1\; {\rm m\cdot s^{-1}}[/tex] to find the change in kinetic energy and hence the work that the net force did on the box:
[tex]\begin{aligned} (\text{Work Done}) &= -(\text{Kinetic energy change}) \\ &= -\frac{1}{2}\, m\, (g\, t\, \sin(15)^{\circ}})^{2} \\ &= -\frac{1}{2}\times 2\; {\rm kg} \times (9.81\; {\rm m\cdot s^{-2}} \times 1\; {\rm s} \times \sin(15^{\circ})^{\circ} \\ &\approx (-6)\; {\rm J}\end{aligned}[/tex].
Question 2:
mark each, 3 marks total)
A box is at rest,the reading on the scale is 250 newtons. Assum that the
acceleration due to gravity remains constant over the entire distance the
elevator can move.
A) When the elevator is moving upward at constant speed, what is the reading on the
scale?
B) When the elevator is accelerating downward at 5 meters per second squared,
what is the reading on the scale?
C) If the elevator cables broke and the elevator fell freely, what would be the reading on
the scale?
A) The reading on the scale is 250 N.
B) The reading on the scale is 122.45 N.
C) The reading on the scale is 0 N.
Given parameters:
Weight of the box is : W = 250 N.
As the acceleration due to gravity is 9.8 m/s², the mass of the box be: m = W/g = 250/9.8 kg = 25.51 kg
A) When the elevator is moving upward at constant speed, there has no acceleration. the reading on the scale remains same and it be 250 N.
B) When the elevator is accelerating downward at 5 meters per second squared, the apparent weight of the box be, W₁ = W -ma = 250 -25.51×5 N = 122.45 N. So, the reading on the scale is 122.45 N.
C) If the elevator cables broke and the elevator fell freely, the elevator is accelerating downward at the same magnitude of acceleration due to gravity, so the apparent weight of the box be, W₁ = W -mg = 0. So, the reading on the scale is 0 N.
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