Which statement describes the effects of forces on an object

What do you think car designers do if the damage caused by a crash test is too severe?

Where is the potential energy throughout the loading, cocking, and releasing of the trebuchet?

Amoving electron has kinetic energy k1. after a net amount of work w has been done on it, the electron is moving one-quarter as fast in the opposite direction. (a) find w in terms of k1. (b) does your answer depend on the final direction of the electron's motion?