Question

A blue block has a mass of 0.92 kg and is stationary on a horizontal frictionless surface. It is struck with a rubber mallet causing it to slide with a speed of 3.1 m/s on the horizontal surface. The mallet is in contact with the block for 23 milliseconds. The blue block collides with a red block with a mass of 0.75 kg and the two blocks stick together. The two blocks slide up a long smooth incline and come to a momentary stop.

1. Sketch the three phases of the motion (mallet strike, collision, ramp). Label with variables.
2. List all known variables and their values.
3. What is the average force of the mallet on the blue block?
4. What is the kinetic energy of the blue block after the mallet strikes it?
5. After the collision, what is the velocity of the 2 blocks stuck together?
6. What is the kinetic energy of the 2 blocks after the collision? Compare this to the kinetic energy before the collision. Explain why they are the same or different.
7. At what vertical height do the blocks stop on the incline?
8. If the incline were a rough surface would the stopping height of the blocks change? If not, explain. If so, how would it change?

Answer 1