Inside a box, a (1.00-mathrm{kg}) ball is gently dropped from a height of (1.00 mathrm{~m}) (Figure P19.21).

Question:

Inside a box, a \(1.00-\mathrm{kg}\) ball is gently dropped from a height of \(1.00 \mathrm{~m}\) (Figure P19.21). The box contains \(1.00 \mathrm{~mol}\) of argon atoms, each having a mass of \(6.63 \times 10^{-26} \mathrm{~kg}\) and moving at an average speed of \(100 \mathrm{~m} / \mathrm{s}\) before the ball is dropped. The ball rebounds elastically against the floor of the box, and so its energy is transferred only to the argon atoms.

(a) What is the average energy of each argon atom before the ball is dropped?

(b) After a long time interval has passed, the ball stops bouncing and rests on the box floor. What is the average speed of the argon atoms now?

Data from Figure P19.21