a 60g tennis ball travelling at 30m/s hit a wall and bounce back at 20m/s. calculate (a)the momentum of the ball before impact (b)the momentum after impact​

Excuse ! extra points plus ! super desperate ! the position of an object does not move relative to a reference point. relative to the reference point the object _. a.) is not moving. b.) is moving.

Which terms describe the purpose of antennas on devices that use radio waves? transmit and receivemodify and amplifyamplify and receivemodify and transmit

An isotope undergoes radioactive decay by emitting radiation that has a –1 charge. what other characteristic does the radiation have?