Solve the following problems on your own paper. Please:

• Show all work.
• Put a box around your final answer to each problem.
• Be sure proper significant figures (SF) used for all answers.
• Separate all solutions with a horizontal line on your paper.
• A random selection of four even problems will be graded for 25 points each.
• Solutions for suggested odd problems can be seen by following links.
• Solutions for even problems will be linked from this page after the due date.

Chapter 8

#2

Convert to mks units before starting. Be careful calculating the angle between F and r here.

#10

The first sentence tells you where the center of mass is located, so when the meter stick is moved to the fulcrum, you should have three forces acting on it: the weight of the stick, the hanging mass, and the normal force from the fulcrum on the stick.

#18

Be sure you distinguish between mass and weight in this problem. All the angles here should be 90 degrees.

#22

This is similar to example 8.7 and problem #20.

#24

This is similar to example 8.8 and problem #25. Answer with 3 SF.

#26

If it makes it easier for you, you can set L = 1.00 in this problem since it will cancel out anyway. Answer with 3 SF.

#32

Use the angular equivalent of Newton's 2nd law. There is only one torque acting on the wheel, and that's from the force of static friction. The normal force is simply equal to the radially inward force exerted by the wet rag. Answer with 2 SF.

#36

See example 8.11 for some help.

#42

Answer with 3 SF.

#44

See example 8.12 for help on this one.

#48

Assume the child is a point mass (for the purposes of calculating angular momentum). Calculate the total angular momentum of the system before and after the child jumps onto the merry-go-round.

#60

Find the tension first by simply doing a free-body force analysis of the sliding mass (you don't need to worry about the pulley in this part). Once you know the tension, analysis of the pulley should be easy.

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Suggested problems:

C1, C2, C3, C4, C5, C7, C9, C11, C12, C14, C15, C17, C18, #1, #3, #4, #5, #6, #7, #8, #9, #11, #12, #15, #16, #17, #19, #20, #21, #23, #25, #27, #28, #29, #30, #31, #33, #34, #35, #37, #38, #39, #40, #41, #43, #45, #46, #47, #49, #50, #51, #52, #53, #54, #55, #61, #62, #63, #70