Physics 213 Quiz 7 Energy 7 pts each Nov. 19, 2004

1. How much work is done by the force F in the F vs x curve below.

2. Given that F = 3i - 4 j and Dr = -2i + j , find the work done by the force F over the displacement Dr.

3. Find the speed with which the 2 kg block strikes the floor. The objects start from rest and the coefficient of friction between the 3 kg block and the table is 0.3. (Assume the pulley and string are massless.)

4. What is the velocity of the 50 kg block sliding down the loop - the - loop ramp at B if the track is friction free.

5. A block slides down a plane and compresses a spring when coming to rest. If the coefficient of kinetic friction between the block and the plane is µ_k = .3 and the spring is compressed 2 m, what is the spring stiffness constant of the spring?