College Physics with MasteringPhysics 7th Edition by Jerry Wilson,Anthony Buffa,Bo Lou

تمرين 120

A hockey puck impacts a goalie's plastic mask horizontally at 122 mi/h and rebounds horizontally off the mask at 47 mi/h. If the puck has a mass of 170 g and it is in contact with the mask for 25 ms, (a) what is the average force (including direction) that the puck exerts on the mask (b) Assuming that this average force accelerates the goalie (neglect friction with the ice), with what speed will the goalie move, assuming she was at rest initially and has a total mass of 85 kg