a 25 kg child is initially riding in a 50 kg cart moving at a speed of 2.0 m/s. the child manages to jump off the back of the cart in such a way that he has no final velocity. what is the resulting velocity of the cart? compare the child's change in momentum to the cart's change in momentum. what additional information would be needed in order to determine the force the child used to jump off the cart?​

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

Four point charges each having charge q are located at the corners of a square having sides of length a. find symbolic expressions for the following. (a) the total electric potential at the center of the square due to the four charges (use any variable or symbol stated above along with the following as necessary: ke.) vtotal= (b) the work required to bring a fifth charge p from infinity to the center of the square (use any variable or symbol stated above along with the following as necessary: w=

In the illustration, which two simple machines are being used to enable the student to reach the door? a. inclined plane and pulley b lever and wheel-and-axle c pulley and lever d wheel-and axle and inclined plane