For a top player, a tennis ball may leave the racket on the serve with a speed of 160 m/s. If the ball has a mass of 0.080 g and is in contact with the racket for about 5 ms (0.005 s), estimate the average force on the ball.

How does the amount of energy required to hold each proton and neutron in the nucleus compare to the energy released when they are removed?

An open cart is moving along a straight frictionless horizontal track. when rain starts falling vertically into the cart, what happens to the speed of the cart?

An astronaut in space cannot use a scale or balance to weigh objects because there is no gravity. but she does have devices to measure distance and time accurately. she knows her own mass is 77.4 kg , but she is unsure of the mass of a large gas canister in the airless rocket. when this canister is approaching her at 3.50 m/s , she pushes against it, which slows it down to 1.30 m/s (but does not reverse it) and gives her a speed of 2.60 m/s . what is the mass of the canister?