A boy of mass 40kg runs upstairs and reaches the roof at height 8m in 5s. (Takeg=10ms−2). Calculate the force of gravity acting on the boy.
A boy of mass 40kg climbs up the stairs and reaches the roof at a height 8m in 5s.Calculate :
1-the force of gravity acting on the boy
2-the work done by him against the gravity
3-the power sent by the boy
(take g=10m 1/s²)