To demonstrate an elastic collision, a teacher places a tennis ball on the floor. she wants to hit the ball so that the following conditions are satisfied. 1. after collision, the tennis ball should roll with the velocity of the ball that hit it 2. at the instant of collision, the ball that hit the tennis ball should stop. what ball should she use? golf ball, tennis ball, basketball, or bowling ball?

A tennis ball

The two balls need to have the same mass to meet this condition.

Neptune is the eighth planet from the sun. it was the first planet to get its existence predicted by  mathematical calculations  before it was actually seen through a telescope on sept. 23, 1846. irregularities in the orbit of  uranus  led french astronomer alexis bouvard to suggest that the gravitational pull from another celestial body might be responsible. german astronomer johann galle then relied on subsequent calculations to   spot neptune via telescope. previously, astronomer galileo galilei sketched the planet, but he mistook it for a star due to its slow motion. in accordance with all the other planets seen in the sky, this new world was given a name from greek and roman mythology — neptune, the roman god of the sea.