Again, combining the heat equations with the heat flow equation, we find that the difference in the temperature between the sample (or Polly) and the cold bath followed an exponential decay, i.e., Tdir = (constant) - Setting time equal to 0 tells us that the prefactor (constant) out front simply is the initial temperature difference. Knowing the decay constant from the previous question and the temperature difference at some later time, then, we can find the time it takes for the difference between the sample's (Polly's) internal temperature and the bath's temperature to reach some specific value. According to the data you took at the (possible) crime scene and your answer to the previous problem, determine how many hours (to the nearest hour) Polly has been deceased (in hours, to the nearest hour)? Again, Polly's and the water bath's initial temperatures were 37°C and 2°C, respectively, and the final temperatures you measured were 13°C and 7°C. Hence, you could determine if foul play may have been involved (say, someone had been seen leaving Polly's apartment a certain time before her body was discovered). 18.703 As you are assisting in the investigation, you notice that Polly's apartment has maintained a cozy temperature even though her heat had been turned off and it's a cold winter's day. (Could this be another clue?) One explanation is that her apartment has nice double pane windows, consisting of two glass panes that are each 4-mm thick sandwiching a well-sealed air gap 6-mm thick. In "steady state", the rate that heat flows through a glass pane equals the rate that heat flows through the air gap in the double pane window (otherwise there would be a net heat flow into the air or window, changing its temperature -- whatever flows into one of these materials must flow out to maintain a given temperature). Since the thermal conductivity of still air (0.025 W/(mºC)] is much smaller than the thermal conductivity of glass (0.80 W/(m°C)], the temperature difference across the double pane window is almost entirely over the air gap. (Again, in this steady state, the rate of heat flow through the glass and air are the same for the double pane window, so if the conductivity of air is much smaller than that of glass, the temperature difference across the air must be much larger than that across the glass for these windows.) Considering this, what is the ratio of the rate of heat flow through a cheap window with a single pane of glass 4-mm thick compared to a nicer double pane window with an air gap of 6 mm if the temperature difference across them is the same (and they have the same areas)? Neglect heat leaks at the edges of the windows.

Answers

Answer 1

the ratio between the rate of heat flow through a cheap window with a single pane of glass that is only 4 mm thick to a nicer double pane window with an air gap of 6 mm is 76.6667.

K[tex]_{glass}[/tex]=0.80 W/m°C

K[tex]_{air}[/tex]=0.025 W/m°C

Q=[tex]\frac{\triangle T}{R_{Th} }[/tex]

(R[tex]_{Th}[/tex])[tex]_{double pane}[/tex]×Q[tex]_{double pane}[/tex]=(R[tex]_{Th}[/tex])[tex]_{single pane}[/tex]×Q[tex]_{single pane}[/tex]

(R[tex]_{Th}[/tex])[tex]_{double pane}[/tex]=∑[tex]\frac{l}{KA}[/tex]

                      =  [tex]\frac{3}{0.8A} +\frac{7}{0.025 A}+\frac{3}{0.8 A}\\[/tex]

                      =[tex]\frac{287.5}{A}[/tex]

(R[tex]_{Th}[/tex])[tex]_{single pane}[/tex]=[tex]\frac{3}{0.8A}[/tex]=[tex]\frac{3.75}{A}[/tex]

[tex]\frac{Q_{single pane} }{Q_{double pane}} =\frac{R_{Th}_{double pane} }{R_{Th}_{single pane}}[/tex]

               = 76.6667

Heat flow, also known as heat transfer, is the movement of thermal energy from a region of higher temperature to a region of lower temperature. This occurs due to the random motion of atoms and molecules within a material. There are three main mechanisms of heat flow: conduction, convection, and radiation. Conduction is the transfer of heat through a material by direct contact, while convection involves the movement of a fluid (such as air or water) due to temperature differences. Radiation is the transfer of heat through electromagnetic waves, such as from the sun or a fire. Heat flow is a fundamental concept in thermodynamics and plays a critical role in many fields, including engineering, physics, chemistry, and biology.

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Related Questions

A small glass bead has been charged 3 60nCA small metal ball bearing 2.60 cm above the bead feels a 1.8 * 10 2 * N downward electric force

Answers

Answer:

The electric field strength at the location of the metal ball bearing is 1.8 * 10^2 N/C.

37. Un beisbolista atrapa una bola 3. 0 s después de lanzarla verticalmente hacia arriba. ¿Con qué rapidez la lanzó y qué altura alcanzó?


A baseball player catches a ball 3. 0 s after throwing it vertically upwards. With what speed did he throw it and what height did it reached?

Answers

Por lo tanto, la pelota fue lanzada con una velocidad inicial de 14.7 m/s y alcanzó una altura máxima de 11.3 m.

¿Cuál es la velocidad?

Generally, Para resolver este problema, necesitamos conocer la relación entre la velocidad inicial con la que se lanza la pelota y la altura máxima que alcanza. Podemos usar las ecuaciones de movimiento para un objeto que se mueve verticalmente con aceleración constante.

Primero, consideremos el momento en que la pelota es lanzada. En ese momento, la velocidad inicial de la pelota es v0, que es lo que estamos buscando. Usando la ecuación de posición vertical:

y = v0t - 1/2gt^2

donde y es la altura alcanzada, t es el tiempo transcurrido, y g es la aceleración debido a la gravedad (-9.8 m/s^2), podemos despejar v0 en términos de y y t:

v0 = (y + 1/2gt^2) / t

Ahora, consideremos el momento en que la pelota es atrapada, 3.0 s después de ser lanzada. Sabemos que en ese momento, la velocidad vertical de la pelota es cero, ya que está en su punto más alto. Usando la misma ecuación de posición vertical, pero estableciendo y = 0 y v = 0, podemos encontrar el tiempo que tarda la pelota en llegar a su altura máxima:

0 = v0t - 1/2gt^2

t = 2v0/g

Sustituyendo este valor de t en la ecuación anterior, podemos encontrar la altura máxima que alcanza la pelota:

y = v0(2v0/g) - 1/2g(2v0/g)^2

y = v0^2/2g

Ahora podemos calcular los valores numéricos. Si asumimos que la altura a la que el jugador atrapa la pelota es la misma que la altura máxima alcanzada por la pelota, y tomamos g = -9.8 m/s^2, entonces:

v0 = (y + 1/2gt^2) / t = (0 + 1/2(-9.8 m/s^2)(3.0 s)^2) / 3.0 s = 14.7 m/s

y = v0^2/2g = (14.7 m/s)^2 / (2(-9.8 m/s^2)) = 11.3 m

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Four small spheres, each charged to +15 nC, form a square 2.0 cm on each
side. From far away, a proton is shot toward the square along a line perpendicular to the square and passing through its center. What minimum initial speed does the proton need to pass through the square of charges?

Answers

The minimum initial speed of the proton needed to pass through the square of charges is 5.09 x 10^6 m/s.

Describe Charge?

Charge is a fundamental physical property of matter that describes the degree to which it interacts with electromagnetic fields. It is an intrinsic property of subatomic particles, such as protons and electrons, that gives rise to electric and magnetic forces.

The basic unit of charge is the Coulomb (C), named after the French physicist Charles-Augustin de Coulomb, who first quantified the electric force between charged objects. A single proton or electron has a charge of approximately 1.6 x 10^-19 Coulombs.

Electric charge is conserved, which means that the total amount of charge in a closed system remains constant over time. Charges can be positive, negative, or neutral, and like charges repel each other, while opposite charges attract each other.

Charge is an important property in many areas of physics, including electromagnetism, quantum mechanics, and particle physics. It is also a crucial concept in many practical applications, such as electronics, power generation, and communication systems.

We can solve this problem using the principle of conservation of energy. The initial kinetic energy of the proton must be equal to the work done by the electrostatic force of the charged spheres on the proton as it passes through the square.

The electrostatic force between two charges q1 and q2 separated by a distance r is given by Coulomb's law:

[tex]F = k * q1 * q2 / r^2[/tex]

where k is the Coulomb constant, which has a value of

[tex]8.99 x 10^9 N m^2 / C^2.[/tex]

Since the four spheres are identical and equally spaced, the electrostatic force on the proton due to each sphere will have the same magnitude and direction. We can calculate the force on the proton due to one sphere and multiply by 4 to get the total force:

[tex]F = 4 * k * q * q_p / r^2[/tex]

where q is the charge on each sphere (+15 nC), q_p is the charge on the proton (-1.6 x 10^-19 C), and r is the distance from the center of the square to the proton's initial position (which we will assume is the same as the distance from the center of the square to the closest sphere, which is sqrt[tex](2)/2 * 0.02 m = 0.0141 m).[/tex]

The work done by the electrostatic force as the proton passes through the square is:

W = F * d

where d is the length of the square (2 cm = 0.02 m).

Equating the initial kinetic energy of the proton to the work done by the electrostatic force, we get:

[tex](1/2) * m * v_i^2 = 4 * k * q * q_p * d / r^2[/tex]

where m is the mass of the proton (1.67 x 10^-27 kg) and v_i is the initial speed of the proton.

Solving for v_i, we get:

[tex]v_i = sqrt(8 * k * q * q_p * d / (m * r^2))[/tex]

Plugging in the values, we get:

[tex]v_i = sqrt(8 * 8.99 x 10^9 N m^2 / C^2 * 15 x 10^-9 C * 1.6 x 10^-19 C * 0.02 m / (1.67 x 10^-27 kg * (0.0141 m)^2))v_i = 5.09 x 10^6 m/s[/tex]

Therefore, the minimum initial speed of the proton needed to pass through the square of charges is [tex]5.09 x 10^6 m/s.[/tex]

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Starting from position x0 = 0 at time t0 = 0, a bicyclist rides in a straight line a distance
x in time t and later is a distance 8x after a time 4t. What is the bicyclist’s constant
acceleration?
A: x/2t^2
B: 7x/3t
C: 6x/5t^2
D: 2x/3t^2

Answers

The acceleration of the bicyclist is a[tex](8x)/(4t) = 2x/3t^2.[/tex]

What is acceleration?

Acceleration is a measure of the rate of change of an object's velocity over a period of time. It is a vector quantity, meaning it has both a magnitude (or size) and a direction. Acceleration can be positive, negative, or zero. A positive acceleration is when a body is speeding up, a negative acceleration is when a body is slowing down, and a zero acceleration is when a body's velocity is constant.

The bicyclist's acceleration can be determined by noting the displacement (x) and the time (t) required to cover that displacement.

The equation for acceleration is a = (change in velocity)/(change in time). In this case, the change in velocity is 8x and the change in time is 4t. Therefore, the acceleration of the bicyclist is a =[tex](8x)/(4t) = 2x/3t^2.[/tex]

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Gulliver's travels which has this fantasy of the whole island of laputa, floating in air.
Could magnets be involved?​

Answers

Answer:

In Gulliver's Travels, the floating island of Laputa is described as being suspended in the air without any visible means of support, and there is no explicit mention of magnets being involved in its levitation. However, it is worth noting that during the 18th century, when Jonathan Swift wrote the novel, there was a growing interest in the properties of magnets and their potential applications in various fields, including navigation, medicine, and even levitation. In fact, some scholars have suggested that Swift may have been inspired by the popular beliefs and speculations about magnets and their possible effects on gravity and motion.

It's not possible to accurately determine how many magnets would be required to make Laputa, the floating island in Gulliver's Travels, suspended in the air because the idea of a floating island is purely fictional and not based on any known physical principles or scientific laws.

Even if we assume that magnets were involved in the levitation of Laputa, it would depend on a wide range of factors, including the size and weight of the island, the strength and orientation of the magnets, the distance between the magnets and the island, and other variables that are not specified in the novel.

Furthermore, magnets by themselves do not have the power to suspend large objects in mid-air. While magnets can be used to create magnetic levitation, or maglev, for small objects like trains or toy cars, the magnetic fields required to lift an entire island would be orders of magnitude larger and more complex than anything currently feasible with our technology.

In short, the idea of Laputa as a floating island is best understood as a literary and imaginative device, rather than a scientifically plausible concept.

That being said, it's important to remember that Gulliver's Travels is a work of fiction and should be enjoyed primarily as a literary creation, rather than a scientific treatise. The idea of a floating island is a fantastical element that serves to underscore Swift's satirical commentary on various aspects of contemporary society and politics. While it is certainly possible to speculate on the mechanics of how such an island might actually levitate, this is not necessarily the most fruitful or rewarding approach to engaging with the novel's themes and meanings.

17. Which of the following supports the idea that the genetic code is common to all living
things?
A. All living things share similar modes of reproduction
B. The same adaptations help all living things survive in the same way.
C. All living things have identical ways of using energy for survival.
D. All living things contain DNA with the same nitrogenous bases.

Answers

Answer:

Explanation:

genetic code us a keyword

different organisms have diff ways in reproducting

different ways of adapting to environments, obtianing energy, etc. It's mainly asking what makes all living things have something in common, like ALL all

When voltage sources are connected in series, the total voltage is equal to the algebraic sum of the individual voltages.a. trueb. false

Answers

The third rule of a series circuit states that the sum of the individual voltages equals the total voltage.

These demonstrate the truth of the previous claim, which reads, "When voltage sources are connected in series, the overall voltage is equal to the algebraic sum of the individual voltages?"

The supply voltage is equal to the total of the component voltages in a series circuit. The voltages across each component in a series circuit are proportional to their resistances. This means that when two similar components are linked in series, the supply voltage is divided equally.

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This equation is known as the ideal gas law, and it can be used to predict the behavior of many gases at relatively low pressure. From this equation, you can see that as the temperature of a gas increases,.

Answers

From the ideal gas law equation ([tex]PV = nRT[/tex]), you can see that as the temperature of a gas increases, either the pressure (P) or the volume (V) of the gas must increase in order to maintain a constant number of moles (n) and a constant gas constant (R).

This can be explained by the kinetic theory of gases, which states that the temperature of a gas is proportional to the average kinetic energy of its molecules. As the temperature increases, the molecules move faster and collide with the walls of the container more frequently and with greater force, increasing the pressure. Alternatively, the molecules can also move further apart, increasing the volume of the gas. In other words, as the temperature of a gas increases, the gas will expand and/or its pressure will increase, assuming the volume or the number of moles of gas are held constant. This relationship is important for many practical applications, such as in the design of engines, refrigeration systems, and industrial processes.

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1. What is the momentum of an 11 kg bowling ball rolling at 4 m/s?

Answers

Any moving object has momentum. The momentum of an 11 kg bowling ball rolling at 4 m/s is 44 kg m/s.

What is momentum?

The momentum is defined as a quantity which is the product of the mass of the particles and its velocity. It is a vector quantity. It has both magnitude and direction. The rate of change of momentum is equal to the force acting on the particle.

The equation of the momentum is given as:

p = mν

= 11 kg × 4 m/s

= 44 kg m/s

Thus the momentum of the bowling ball is 44 kg m/s.

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T/F : when two batteries are connected as a series additive power source, they produce a voltage that is less than either of the batteries connected by itself.

Answers

This statement is False as batteries connected as a series additive power source doesn't produce a voltage that is less than either of the batteries connected by itself.

The battery is a tool for powering electrical appliances that is made up of one or more electrochemical cells with external connections. Batteries in a specific circuit are either connected in series or parallel depending on how many there are. It is essential to comprehend the differences between series and parallel connections since they affect how batteries function in various applications. Batteries can be linked in both series and parallel configurations. A battery with this configuration is known as a series-parallel battery. Occasionally the load may need more voltage and current than a single battery cell is capable of providing. The desired number of batteries are coupled in series to produce the necessary current, and these series combinations are connected in parallel to produce the necessary load voltage.

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The momentum of an object is calculated by?​
A.multiplying mass by acceleration.
B.dividing force by acceleration.
C.dividing mass by velocity.
D.multiplying mass by velocity.​

Answers

D. Multiplying mass by velocity.

The momentum of an object is a measure of its motion and is defined as the product of its mass and velocity. It is a vector quantity, meaning it has both magnitude and direction.

The formula for momentum is given by p = mv, where p is the momentum, m is the mass of the object, and v is its velocity. So, the momentum of an object can be calculated by multiplying its mass by its velocity.

Option A is incorrect because momentum is not simply the product of mass and acceleration. Option B is incorrect because force is not directly related to momentum. Option C is incorrect because dividing mass by velocity does not give momentum, it gives the velocity of the object.

If the mass of the cart is 250 kg, solve for PE at A (height 100 m) and D
(height 75 m). Velocity at A is 0, solve for velocity at location D.

Answers

To solve for the potential energy at points A and D, we need to use the formula for gravitational potential energy:

[tex]PE = mgh[/tex]

What is potential energy?

At point A, the height is h = 100 m and the mass of the cart is m = 250 kg. The acceleration due to gravity is g = 9.81 m/s^2. Therefore, the potential energy at point A is:

[tex]PE_A = mgh = (250 kg)(9.81 m/s^2)(100 m) = 245250 J[/tex]

At point D, the height is h = 75 m and the mass of the cart is still m = 250 kg. The potential energy at point D is:

[tex]PE_D = mgh = (250 kg)(9.81 m/s^2)(75 m) = 183937.5 J[/tex]

To solve for the velocity at point D, we can use the conservation of energy principle. At point A, the cart has only potential energy (no kinetic energy), so the total mechanical energy is equal to the potential energy:

[tex]E_A = PE_A = 245250 J[/tex]

At point D, the cart has both potential energy and kinetic energy. Therefore, the total mechanical energy is the sum of the potential and kinetic energies:

[tex]E_D = PE_D + KE_D[/tex]

where [tex]KE_D[/tex] is the kinetic energy at point D, and it is what we want to find.

According to the conservation of energy principle, the total mechanical energy at point D must be equal to the total mechanical energy at point A (assuming no non-conservative forces such as friction act on the cart between A and D). Therefore:

[tex]E_A = E_D[/tex]

Substituting in the values we have calculated:

[tex]245250 J = 183937.5 J + KE_D[/tex]

Solving for [tex]KE_D[/tex], we get:

[tex]KE_D = 61212.5 J[/tex]

To find the velocity at point D, we can use the formula for kinetic energy:

[tex]KE = (1/2)mv^2[/tex]

where KE is the kinetic energy, m is the mass of the object, and v is the velocity of the object.

Substituting in the values we have calculated, we get:

[tex]KE_D = (1/2)mv_D^2Solving for v_D, we get:v_D = sqrt((2KE_D) / m) = sqrt((2(61212.5 J)) / (250 kg)) = 17.6 m/s[/tex]

Therefore, the velocity at point D is 17.6 m/s.

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An object has an acceleration of 25.3 m/s/s. If the mass of the object is Increased by a factor of 2.91, then the new
acceleration would be
m/s/s. Assume that the force exerted on the object remains constant. Round your
answer to 3 significant figures

Answers

The new acceleration of the object is therefore a' = a / 2.91 = 25.3 m/s/s / 2.91 = 8.69 m/s/s to 3 significant figures.

How did we get the value?

We know that the force exerted on an object is equal to its mass times its acceleration, or F = m * a. If the force exerted on the object remains constant, then the new acceleration of the object after its mass has been increased by a factor of 2.91 can be calculated as follows:

a' = F / (m * 2.91) = F / m'

Where m' is the new mass of the object.

Substituting the original acceleration and mass into the equation, we get:

a' = F / (m * 2.91) = F / (m * 2.91) = (m * a) / (m * 2.91) = a / 2.91

The new acceleration of the object is therefore a' = a / 2.91 = 25.3 m/s/s / 2.91 = 8.69 m/s/s to 3 significant figures.

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Newton’s second law of motion states the relationship of mass, acceleration, and force.  It says that ______

A.force equals mass divided by acceleration
B. force equals mass multiplied by acceleration
C. acceleration equals force multiplied by mass
D. every object attracts every other object in the universe​

Answers

Answer:

B. force equals mass multiplied by acceleration

Explanation:

Newton's second law of motion states that the acceleration of an object equals the net force acting on the object divided by the object's mass. According to the second law, there is a direct relationship between force and acceleration and an inverse relationship between mass and acceleration.

Newton's second law of motion is F = ma, or force is equal to mass times acceleration.

A man is standing on the shore of a beach, up to his knees in water. Every 5 seconds a wave breaks on him. What is the period of the wave?.

Answers

Answer:

The period of a wave refers to the time it takes for a complete wave cycle to occur, from crest to crest or from trough to trough. In this scenario, you have specified that every 5 seconds a wave breaks on the man, so the period of the wave is 5 seconds.

Explanation:

pls mark brainlist and np

Answer:

Explanation:

= 4 Hz

As an example, a wave with a period T = 0.25 s takes ¼ of a second to complete a full vibration cycle (crest - trough - crest) at a certain location and thus performs four vibrations per second. Hence its frequency is f = 4 Hz.

Use Newton's Second Law Analysis combined with torque to solve the following problem.
Three masses are attached to a uniform meter stick, as shown in the figure to your right. The mass of the meter stick is 200.0 g and the masses to the left of the fulcrum are m1 = 75.0g and m2=100.0g. Don't forget the meter stick has mass.

a) What is mass m3 that balances the system when it is attached at the right end of the stick. The resulting system is balanced.

b) What is Force the fulcrum exerts on the meter stick at point S?

Answers

5.8N. is the correct answer .

What is Torque ?

In physics and engineering, "torque" is a measure of the twisting force that can cause an object to rotate around an axis or pivot point The magnitude of torque depends on both the force being applied and the distance between the axis of rotation and the point of application of the force. The direction of the torque is determined by the right-hand rule, with the thumb pointing in the direction of the applied force and the fingers curling in the direction of rotation. Torque is a key concept in the study of mechanics and is used in a wide range of applications, such as engines, motors, and machines.

τ1=+r1w1sin90=+r1m1g(counterclockwise rotation, positive sense)

τ2=+r2w2sin90°=r2m2g(counterclockwise rotation, positive sense)

τ=+rwsin90°=+rmg(gravitational torque)

τS=rSFSsinθS=0(because S=0cm)τ3=−r3w3sin90°=−r3m3g(clockwise rotation, negative sense)

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A bag of cookies 6 oatmeal cookies, 5 pecan cookies and 1 peanut butter cookies. Mary selects 2 cookies at random. What is the probability that the selected 2 oatmeal cookies?.

Answers

The probability that the selection is made of 2 oatmeal cookies are 1/6.

As per given data in the question:

Oatmeal cookies - 6

Pecan Cookies - 5

Peanut butter cookies - 1

Total cookies in the jar - 12

The probability that the selection is of 2 oatmeal cookies, it is as follows:

P (oatmeal cookies) = 2/12 = 1/6

Probability deals with the likelihood of an event or phenomena occurring and is quantified as a number between 0 and 1 inclusive, where 0 indicates an impossible chance of occurrence and 1 denotes the certain probable outcome of an event.

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According to dalton's law of partial pressures, the pressure of oxygen in dry air would be.

Answers

The pressure of oxygen in dry air at standard atmospheric pressure is approximately 22.3 kilopascals.

What is Dalton's law of partial pressure?

The overall pressure of a gas mixture is equal to the sum of the partial pressures of each gas in the mixture, according to Dalton's law of partial pressures.

With a few other gases present in trace levels, nitrogen and oxygen make up roughly 78% and 21% of the atmosphere, respectively, in dry air.

As a result, using Dalton's law, the pressure of oxygen in dry air can be computed as follows:

Total pressure of dry air equals the pressure of nitrogen, oxygen, and any additional gases.

Total pressure of dry air = pressure of nitrogen + pressure of oxygen

Pressure of oxygen = Total pressure of dry air - pressure of nitrogen

= 101.3 kPa - 79 kPa

= 22.3 kPa

Thus, this is the pressure of oxygen in dry air.

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A hollow metal sphere has inner radius a and outer radius b. The hollow sphere has charge +2 Q. A point charge + Q sits at the center of the hollow sphere.


Determine the magnitude of the electric field in the region r≤a

Answers

The magnitude of the electric field in the region r≤a is zero.

What is Point Charge?

A point charge is a theoretical charge that is assumed to be located at a single point in space, with all of its electric charge concentrated at that point. It is an idealized model that is often used to simplify calculations in electromagnetism. A point charge can be either positive or negative and is characterized by its electric charge, which is a fundamental property of matter. The electric field created by a point charge decreases with distance from the charge, following an inverse square law. The concept of a point charge is often used in electrostatics, where the charge distribution of an object can be approximated as a collection of point charges.

Inside the hollow metal sphere (i.e., for r≤a), the electric field is zero because the excess charge +2Q on the sphere redistributes itself to cancel out the electric field due to the central charge +Q.

This can be shown using Gauss's Law. A spherical Gaussian surface of radius r≤a, centered at the center of the sphere and inside the metal shell, encloses only the point charge +Q. By symmetry, the electric field is radial and has the same magnitude at every point on the Gaussian surface. By Gauss's Law, the total electric flux through the surface is proportional to the charge enclosed by the surface. Since there is no charge inside the surface (because the excess charge on the metal sphere cancels out the charge inside it), the total electric flux through the surface is zero. Therefore, the electric field inside the hollow metal sphere is zero.

Thus, the magnitude of the electric field in the region r≤a is zero.

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A ball strikes the floor for 0.0105 s and experiences a change in momentum of 1.52 kg·m/s. What is the force experienced by the ball?*
A.1.60 N
b. 144.76 N
c.23.82 N
d. 0.016 N​

Answers

Answer: B is right

Explanation:  Change in Momentum / Time Therefore, the force experienced by the ball is: Force = 1.52 kg·m/s / 0.0105 s Force = 144.76 N Answer: B. 144.76 N

A planet of mass 6 × 10^24 kg is at location ‹ −3 × 10^11, 8 × 10^11, 0 › m. A star of mass 7 × 10^30 kg is at location ‹ 7 × 10^11, −5 × 10^11, 0 › m. What is the force exerted on the planet by the star? (It will probably be helpful to draw a diagram, including the relevant vectors.)

Answers

The force exerted on the planet by the star is 3.52 x 10²² N.

What is Newton's law of gravitation?

Newton's law of gravitation is a fundamental law of physics that describes the force of gravitational attraction between two objects with mass. The law was first described by Sir Isaac Newton in 1687 and is one of the three laws that form the basis of classical mechanics.

To find the force exerted on the planet by the star, we can use Newton's law of gravitation, which states that the force between two objects with masses M1 and M2 and a distance r between their centers is given by:

F = G × M1 × M2 / r²

where G is the gravitational constant, which has a value of 6.67 x 10⁻¹¹ N*m²/kg².

We can first calculate the distance between the planet and the star by taking the difference between their positions:

r = √[(7 x 10¹¹ - (-3 x 10¹¹))² + (-5 x 10¹¹ - 8 x 10¹¹)² + 0²] = 1.38 x 10¹² m

Next, we can calculate the force exerted on the planet by the star:

F = G × M1 × M2 / r²

F = (6.67 x 10⁻¹¹ N*m²/kg²) × (6 x 10²⁴ kg) × (7 x 10³⁰kg) / (1.38 x 10¹² m²)

F = 3.52 x 10²²N.

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In what units do we measure force

Answers

Answer:

Newtons

Explanation:

The SI unit of force is the newton.

The tires of a car makes 73 revolutions as the car reduces its speed uniformly from 94.0 km/h to 60.0 km/h. The tires have a diameter of 0.84 m.

Part C: If the car continues to decelerate at this rate, how far does it go? Find the total distance.

Answers

Answer:

0.3252km = 325.2m

Explanation:

if this answer is correct only. i can explain the method.

A heart defibrillator being used on a patient has an RC time constant of 23.0
ms due to the resistance of the patient and the capacitance of the defibrillator. If the defibrillator has an 9.75
μF capacitance, what is the resistance of the path through the patient?
If the initial voltage is 12.0
kV, how long does it take to decline to 115
V?

Answers

A heart defibrillator being used on a patient has an RC time constant of 23.0 ms. ,If the defibrillator has a 9.75 μF capacitance, then it takes approximately 21.1 ms for the initial voltage of 12.0 kV to decline to 115 v.

What is the calculation of the voltage of the defibrillator ?

The calculation is explained below,

RC = resistance x capacitance

resistance = RC / capacitance

resistance = (23.0 ms) / (9.75 μF) = 2,359 ohms

Time for  the initial voltage of 12.0 kV to decline to 115 V,

V(t) = V₀ ×  [tex]{e}^(^-^t^/^R^C^)[/tex]    ( here, V(t)=voltage at time t, V₀= initial voltage, e= constant= 2.71828, t= time, R= resistance, C= capacitance)

For t= -RC × ln(V(t) / V₀)

t = - (23.0 ms) × ln(115 V / 12.0 kV) = 21.1 ms

Hence, a heart defibrillator being used on a patient has an RC time constant of 23.0 ms. ,If the defibrillator has a 9.75 μF capacitance, then it takes approximately 21.1 ms for the initial voltage of 12.0 kV to decline to 115 v.

 

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Find a function that models the simple harmonic motion having the given properties. Assume that the displacement is at its maximum at time t = 0.
amplitude 6.45 in., frequency 30 Hz

Answers

The function for the simple harmonic motion having the given properties. Assume that the displacement is at its maximum at time t = 0 is y = 6.45 cos(60π*t).

Moving an object back and forth along a line is known as simple harmonic motion.

See a pendulum, for instance. It follows the same path when we swing it back and forth. Oppositions are what these motions are. A simple harmonic motion example is the oscillations of a pendulum.

[tex]y=Acos(Bt)[/tex]

has amplitude |A| and period 2π/B, and reaches its maximum at t=0.

So we choose A = 6.45

Period = 1/frequency

Period = 2π/B = 1/30

2π/B = 1/30

B = 60π

y = A.cos(Bt)

y = 6.45 cos(60π*t)

Therefore, The function for the simple harmonic motion is y = 6.45 cos(60π*t).

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Explain how the state of consciousness ( focused awareness, drifting consciousness,divided consciousness, and altered consciousness) differs from each other?

Answers

Consciousness is our current awareness of ourselves and of the world around us.

Focused awareness is a state of heightened alertness we experience when completely absorbed in a task or activity.

Drifting consciousness is a state of awareness characterized by drifting thoughts or mental imagery.

Divided consciousness is a psychological state in which one's consciousness is split into distinct components, possibly during hypnosis

An altered consciousness is a change in one's normal mental state as a result of trauma or accident or induced through meditation, drugs, some foods, etc.

What is the state of consciousness?

Our level of awareness of internal events and external surroundings is known as a state of consciousness. States of consciousness can also be divided into two broad categories – normal waking consciousness and altered states of consciousness.

What are the seven states of consciousness?

The seven states of consciousness are: waking, dreaming, sleeping, transcendental consciousness, cosmic consciousness, God consciousness, and unity consciousness.

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A piece of gold-alminium alloy weighs 49N. When suspended from a spring balance and submerged in water it weighs 39.2N. What is the weight of Gold in the alloy the specific gravity of gold is 19.3 and that if aluminium is 2.5? ​

Answers

Answer:

The mass of the water in 1 kg (9.8 N = m (9.8 m/s/s)),

Thus the volume of the water is 1000 ml.

5 = (Mau + Mal)/(Vau + Aal)  

(Density = total mass to the total volume)

We know that:

19.2 = Mau/Vau and 2.5 = Mal/Val.  

We have to find the volume. Therefore,

5Val + 5Vau = Mau + Mal

5(Mal/2.5) + 5(Mau/19.2) = Mau + Mal

Mal = 0.74 Mau

5 kg = M(au) + (1/.74)M(au)

=> M(au) = 2.13 kg

Weight of gold = 20.8 N

hence the weight of the gold is 20.8 N

Two capacitors are connected in parallel across a 60 Hz supply. One of the capacitors is rated at 50 microfarads and has a current of 2.34 A through it.

Determine the capacitance of the second capacitor if the current through it is 0.40 A.

Answers

The capacitance of the second capacitor is 5.1 microfarads.

What is capacitance?

Capacitance is the ability of an electrical component, such as a capacitor, to store an electrical charge. The amount of charge that can be stored is related to the capacitance, which is measured in Farads. The larger the capacitance, the more charge a capacitor can store.

The total capacitance of two capacitors connected in parallel is equal to the sum of the individual capacitances. That is, C_total = C1 + C2.
We know the value of one of the capacitors, C1, to be 50 microfarads, and we know the current through it, I1, to be 2.34 A.
Since capacitance and current are inversely proportional, we can use this relationship to solve for the capacitance of the second capacitor, C2.
C2 = C1 * (I2 / I1)
where I2 is the current through the second capacitor, which we know to be 0.40 A.
Plugging in the values, we get:
C2 = 50 * (0.4 / 2.34)
C2 = 5.1 microfarads
Therefore, the capacitance of the second capacitor is 5.1 microfarads.

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A transformer has a primary coil with 400 turns of wire and a secondary coil with 1,600 turns. An AC generator connected across the primary coil has a voltage given by the function Δv = (180 V)sin(t).
What rms voltage (in V) is measured across the secondary coil?

Answers

The voltage across the secondary coil is related to the voltage across the primary coil by the turns ratio of the transformer. The turns ratio is defined as the ratio of the number of turns in the secondary coil to the number of turns in the primary coil. In this case, the turns ratio is 1600 turns / 400 turns = 4.

The rms voltage across the secondary coil is given by the following formula:

V_secondary_rms = V_primary_rms * turns ratio

where V_primary_rms is the rms voltage across the primary coil.

The rms voltage across the primary coil is given by the following formula:

V_primary_rms = Δv / (2^0.5) = Δv / 1.41

where Δv is the peak voltage of the AC generator.

Substituting Δv = 180 V and evaluating the above formula, we get:

V_primary_rms = 180 V / 1.41 = 127.46 V

Substituting the value of V_primary_rms into the equation for the secondary coil, we get:

V_secondary_rms = 127.46 V * 4 = 509.84 V

So, the rms voltage measured across the secondary coil is 509.84 V.

ivy has a mixture of salt and sand. she decided to separate the two substances by pouring the mixture into a jar of water. how could ivy speed up the separation of the two substances?

Answers

Ivy has a mixture of salt and sand, and she wants to separate the two substances by pouring the mixture into a jar of water so she can speed up the separation of salt and sand by stirring the mixture to increase the surface area of the particles, and then salt will dissolve in water with sand left behind or by using the filtration this can be done.

What is the process to separate solutes from mixtures?

There are numerous methods for separating the solutes, such as stirring the mixture to increase the surface area of the particles, allowing the mixture to settle, or using the filter to separate salt and sand from the solution before salt dissolving in water.

Hence, Ivy has a mixture of salt and sand, and she wants to separate the two substances by pouring the mixture into a jar of water so she can speed up the separation of salt and sand by stirring the mixture to increase the surface area of the particles, and then salt will dissolve in water with sand left behind or by using the filtration this can be done.

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