Question

A 90.00 kg hockey goalie, at rest in front of the goal stops a 160 g puck that is traveling at 30.00 m/s. At what speed do the goalie and puck travel after the save? If the coefficient of friction between the skate and ice is 0.030, how far will the goalie move?

Answer 1

0.160 * 30 = (0.160 + 90)v
v = 4.8 / 90.16 = 0.0532 m/s

friction force = mu m g = 0.030 * 90.16 * 9.81 = 26.5 Newtons
work done = 26.5 d Joules
initial kinetic energy = (1/2)(90.16)(.0532^2) = 0.128 Joules
so
d = 0.128 /26.5 = 0.00481 meters or 4.81 millimeters, not far