Two mental balls with the same mass hang so that they are touching each other. The ball on the left is pulled to the side and released. What will happen when when it swings back and hits the ball on the right?

Question

1. both balls will swing to the right
2. the ball on the right will swing to the right
3. both balls will swing to the left
4. the ball on the left will stop, and the ball on the right will remain still

Answer 1

When the left ball is pulled to the side and released, it swings back down due to gravity. When it collides with the ball on the right, which is initially at rest, the momentum and energy will be transferred from the left ball to the right ball.

Assuming the collision is elastic (which is typical in such physics problems involving identical objects), the left ball will come to a stop after the collision, while the right ball will swing to the right.

Thus, the correct answer is: 2. the ball on the right will swing to the right.