Mastering Physics Solutions: Electric Fields and Equipotential Surfaces

Mastering Physics Solutions: Electric Fields and Equipotential Surfaces

On February 6, 2012, in Chapter 16: Electric Potential, Energy, and Capacitance, by Mastering Physics Solutions

Part A = 0 J
Part B = 1 J
Part C = greater than the magnitude of the electric field at point B.

What is the work WAB done by the electric force to move a 1 C charge from A to B?
What is the work WAD done by the electric force to move a 1 C charge from A to D?
The magnitude of the electric field at point C is

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Mastering Physics Solutions: Energy Stored in a Charge Configuration

Mastering Physics Solutions: Energy Stored in a Charge Configuration

On February 4, 2012, in Chapter 16: Electric Potential, Energy, and Capacitance, by Mastering Physics Solutions

Part A = 0
Part B = figure a

Four point charges, A, B, C, and D, are placed at the corners of a square with side length L. Charges A, B, and C have charge + q, and D has charge – q.

If you calculate W, the amount of work it took to assemble this charge configuration if the point charges were initially infinitely far apart, you will find that the contribution for each charge is proportional to (kq2)/L. In the space provided, enter the numeric value that multiplies the above factor, in W.
Which of the following figures depicts a charge configuration that requires less work to assemble than the configuration in the problem introduction? Assume that all charges have the same magnitude q.

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Mastering Physics Solutions: Exercise 5.25

Mastering Physics Solutions: Exercise 5.25

On December 24, 2011, in Chapter 05: Work and Energy, by Mastering Physics Solutions

Part A = 1.9J Click to use the calculator/solver for this part of the problem
Part B = 2.9J Click to use the calculator/solver for this part of the problem

A particular spring has a force constant of 1.5×103 N/m. How much work is done in stretching the relaxed spring by 5.0 cm? How much more work is done in stretching the spring an additional 3.0 cm?

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Mastering Physics Solutions: Pulling a Block on an Incline with Friction

Mastering Physics Solutions: Pulling a Block on an Incline with Friction

On December 24, 2011, in Chapter 05: Work and Energy, by Mastering Physics Solutions

Part A = -24.5J Click to use the calculator/solver for this part of the problem
Part B = 700J Click to use the calculator/solver for this part of the problem
Part C = -24.5J
Part D = 700J

A block of mass 1.00 kg sits on an inclined plane as shown. A force of magnitude 70.0N is pulling the block up the incline. The coefficient of kinetic friction between the plane and the block is 0.500. The inclined plane makes an angle 60.0 degrees with the horizontal. What is the total work Wfric done on the block by the force of friction as the block moves a distance 10.0 m up the incline?

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Mastering Physics Solutions: Work and Kinetic Energy

Mastering Physics Solutions: Work and Kinetic Energy

On December 24, 2011, in Chapter 05: Work and Energy, by Mastering Physics Solutions

Part A = It is equal to the kinetic energy of the lighter block.
Part B = twice as fast
Part C = The heavy block must be pushed 4 times farther than the light block.

Which of the following statements is true about the kinetic energy of the heavier block after the push?
Two blocks of ice, one four times as heavy as the other, are at rest on a frozen lake. a person pushes each block the same distance . ignore friction and assume that an equal force is exerted on each block.

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Mastering Physics Solutions: Understanding Work Done by a Constant Force

Mastering Physics Solutions: Understanding Work Done by a Constant Force

On December 22, 2011, in Chapter 05: Work and Energy, by Mastering Physics Solutions

Part A = A. Positive
Part B = C. Zero
Part C = B. Negative
Part D = C. Zero
Part E = W = 0J
Part F = W = wdcos(90 – φ)
Part G = W = 0
Part H = D. None of these

Which of the following statements accurately describes the sign of the work done on the box by the force of the push? Which of the following statements accurately describes the sign of the work done on the box by the normal force? Which of the following statements accurately describes the sign of the work done on the box by the force of kinetic friction? Which of the following statements accurately describes the sign of the work done on the box by the force of gravity (i.e., the weight)?

You have just moved into a new apartment and are trying to arrange your bedroom. You would like to move your dresser of weight 3,500 N across the carpet to a spot 5 m away on the opposite wall. Hoping to just slide your dresser easily across the floor, you do not empty your clothes out of the drawers before trying to move it. You push with all your might but cannot move the dresser before becoming completely exhausted. How much work do you do on the dresser?

A box of weight w is sliding down a frictionless plane that is inclined at an angle φ above the horizontal, as shown in the figure (Part F figure) . What is the work done on the box by the force of gravity if the box moves a distance d?

The planet Earth travels in a circular orbit at constant speed around the Sun. What is the net work done on the Earth by the gravitational attraction between it and the Sun in one complete orbit?

A block of mass m is pushed up against a spring with spring constant k until the spring has been compressed a distance x from equilibrium. What is the work done on the block by the spring?

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