Blocks A (0.1 kg) and B (0.4 kg) ride on a frictionless level surface in one dimension and have Velcro on their sides, so that they stick when they touch. Block B is also connected to a massless, ideal spring (k = 50 N/m) which extends horizontally and is connected to a wall. Initially Block B is at rest, and block A approaches from the left (see figure).
Immediately after the hit, the two blocks are going 0.2 m/s. They then oscillate. Consider the following three statements in questions 19 and 20.
I. Momentum is conserved.
II. Kinetic energy is conserved.
III. The sum of kinetic and spring potential energy is conserved.
Section C A research and development lab has just built a prototype for a potato peeler. It has many moving parts, but one particular part, the blade patroler, is not supposed to move. When the researchers turn on the machine, they notice that this piece vibrates a little at first, then more, until it is flopping around uselessly. If resonance is responsible for this phenomenon, what can you conclude? Consider the following statements.
I. There is a weak connection between this vibration and another vibration.
II. There is a strong connection between this vibration and another vibration.
III. The two vibrations have similar or equal frequencies.