A tennis player throws a .02 kg ball against the wall at 10m/s. It hits the wall and comes back at -17 m/s. His foot was in contact with the ball for .021 sec. What was the force of the kick? Remember what to do with two velocities.

What is the length x of the side of the triangle below? (hint: use the cosine function)

Boxing gloves are padded to lessen the force of a blow. (a) calculate the force exerted by a boxing glove on an opponent’s face, if the glove and face compress 7.50 cm during a blow in which the 7.00-kg arm and glove are brought to rest from an initial speed of 10.0 m/s. (b) calculate the force exerted by an identical blow in the gory old days when no gloves were used and the knuckles and face would compress only 2.00 cm. (c) discuss the magnitude of the force with glove on. does it seem high enough to cause damage even though it is lower than the force with no glove?

1.what is where an object is located 2. what is how fast an objects speed is changing 3. what is how fast an object is moving