PHY11 Final Examination SET A

1. A 2.00-kg block, on a horizontal ledge, is pressed against a horizontal spring of force constant 500 N/m and compresses it by 0.200 m (See figure below). The block is released and the spring propels it forward toward the edge of the ledge. The coefficient of kinetic friction between the block and the ledge is 0.250. (a) What is the speed of the block when it reaches the edge of the ledge? (b) If the ledge is 5.00 m above the ground, what is the speed of the block when it strikes the ground?

2. Two balls of the same mass had an off-center collision. The first ball has an initial speed of 10.0 m/s in the +x direction and the second ball is initially at rest. After the perfectly elastic collision, the 1st ball is deflected 30o from its original direction. Determine the speeds of the balls after the collision.

3. A uniform meterstick has a mass of 0.100 kg. (a) Find the moment of inertia of the meterstick about an axis perpendicular to it and through

the 20.0-cm mark. Use either the parallel-axis theorem or I=∫r2 dm. (b) If a constant force of 10.0 N is then applied perpendicularly at the 100-cm mark, what will the angular acceleration of the meterstick be?

4. Water enters a house at a gauge pressure of 4.00 x 105 Pa through an inlet pipe of cross-section area 5.00 cm2. A pipe with half the diameter of the inlet pipe leads to a second floor bathroom faucet 4.50 m above. The faucet in the bathroom can fill a 12.0-L container in one minute. (a) What are the flow speeds in the bathroom faucet and in the inlet pipe? (b) What is the gauge pressure in the bathroom?

5. A block of mass 0.250 kg is attached to one end of a horizontal spring of force constant 100 N/m. The other end of the spring is attached to the wall and the block is on a frictionless horizontal surface. The block is then pulled 0.150 m from the equilibrium position and then released. Find (a) the period of oscillation of the block. (b) the position, velocity, and acceleration of the block at t = 0.125 s.

4.00 m

0.500 m

m