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1. Starting from rest, a block of mass m slides down a frictionless incline at θ degrees from the horizontal. At the bottom of the incline, there is a spring which of constant k. The block travels down the incline a distance L until maximum compression of the spring. Find k in terms of the other quantities given and g. You MUST justify any equation you use AND invoke which law(s) they are coming from (10 pts)

L

PHY205 Ch7-13 ReviewPr

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1. A roller coaster car start from the top at h and v=0 and goes

through a loop-the-loop of radius R as shown in picture. What is the speed at the top of the loop? What is the normal force of the seat acting on the butt of the rider at that point? What must be so that the rider doesn’t fall off if she is not attached? (17pts)

h R

PHY205 Ch7-13 ReviewPr

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1. The 1.2m arm of a ballistic pendulum rises by 30o after a 0.005kg bullet gets

embedded in its wooden end. The arm is massless and the wooden block has a mass M=20kg. How fast was the bullet travelling? (justify all equations and state the laws you are using and why they apply) (14pts) How much energy was dissipated by the wood? (3pts)

PHY205 Ch7-13 ReviewPr

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I (m=75kg) am in outer space on a space “walk” when I notice that my space ship is drifting away from me at 1.5m/s. When I notice this the space ship is 25m away from me. I have 10 minutes worth of air in my tank. Things are looking bad! But I realized that I have a 2kg tool that I took on the walk with me. How fast and in what direction do I have to throw the tool (state what law you are using and justify your steps) (16pts)

PHY205 Ch7-13 ReviewPr

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Starting from rest, a block travels down a frictionless incline at from the horizontal, for a distance D and onto a horizontal surface with kinetic coefficient of friction . How far does the block travel on the horizontal before stopping. (16pts)

PHY205 Ch7-13 ReviewPr

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Work out the gravitational sling shot effect. (Make sure to state assumption and explain delicate steps) (16pts)

PHY205 Ch7-13 ReviewPr

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You want to close your dorm room without moving by throwing something at it. Your choice is your bouncy elastic 1Lb shoe, or a 1Lb ball of sticky play-dough that will stick to the door. Which one will require the least effort (you must support your answer with equations and the laws that they translate) (10pts)

PHY205 Ch7-13 ReviewPr

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A ball of mass m=0.12kg is released from a height h1=1.2m and bounces on the floor to come back to a height h2=0.8m. The ball is in contact with the floor for t=0.05s). Is the collision elastic (why/why not)? Is momentum conserved during the collision (justify)? How much momentum is transferred to the floor/Earth during the collision (state laws that apply)? What is the average force that the floor exerts on the ball? What is the acceleration imparted to the ball by that force (express your answer in g’s)? (16 pts)