A football player with a mass of 110 kg runs into a stationary tackling sled that has a mass of 250 kg. Both the player and sled move together and come to rest 25 cm from the impact. If the coefficient of kinetic friction between the sled and the ground is 0.50, what was the initial speed of the football player

Copper has free electrons per cubic meter. a 71.0-cm length of 12-gauge copper wire that is 2.05 mm in diameter carries 4.85 a of current. (a) how much time does it take for an electron to travel the length of the wire? (b) repeat part (a) for 6-gauge copper wire (diameter 4.12 mm) of the same length that carries the same current. (c) generally speaking, how does changing the diameter of a wire that carries a given amount of current affect the drift velocity of the electrons in the wire?

Eddy whose mass is 55kg climbs up the 1.50 meter high stairs in 2s.calculate eddy’s power rating

When you push downward on a book at rest on a table, you feel an upward force. does this force depend on friction? defend your answer.