You (50.0-kg mass) skate on ice at 5.0 m/s to greet your friend (40.0-kg mass), who is standing still, with open arms. as you collide, while holding each other, with what speed do you both move off together? how much kinetic energy is lost in this collision?

Aray of light traveling parallel to the principal axis of a concave mirror will be reflected through the mirror's

Henry, whose mass is 95 kg, stands on a bathroom scale in an elevator. the scale reads 830 n for the first 2.4 s after the elevator starts moving, then 930 n for the next 2.4 s. part a what is the elevator's speed 4.8 s after starting? express your answer with the appropriate units.

Two masses are connected by a rope that hangs over a pulley as shown below. the pulley is a uniform cylinder of radius 푅=0.381meters and mass 푀=3.1푘푔. initially 푚"is on the ground and 푚#rests 2.5 meters above the ground. if the system is released, use conservation of energy to determine the speed of 푚#just before it strikes the ground. assume the pulley bearing is frictionless.