* a boy standing beside a tall building throws a ball straight up with an initial velocity 15m\s
A) hoe high will the ball rise
B) how long will it take for the ball to reach its max
سوال 4
an ice hockey player stikkes a puck of mass 0,17 kg with his stick accelerating it along the ice from rest to a speed of a 20 m\s over a distance of 0,5 m
what firce must he exert if the frictional between the puck and the ice negligible..