(a) Define the term 'average power'. (b) When a player hits a football, it moves along the curved path and then falls to the ground, Calculate the work done by the force of gravity on the football


#1

(a) Define the term ‘average power’.
(b) When a player hits a football, it moves along the curved path and then falls to the ground, Calculate the work done by the force of gravity on the football.
© Two friends Ram and Shyam, each having zveight of 40 kg, go for rock climbing. Ram climbs to a height of 3 m in 10 s and Shyam covers the same height in 12 s. Is the work done by Ram and Shyam equal or not ? Compare the power of Ram and Shyam.


#2

(a) Average power is defined as the ratio of total work done to the total time taken.
(b) When a player hits a football, it moves along the curved path and then falls to the ground, then work done by the force of gravity
W = mgh.
Since h = 0, therefore, W = 0
© Work done by Ram and Shyam is same because both have same weight and both climb equal height.
Power of Ram = PE / t = 40 x 9.8 x 3 /10
= 117.6 W
Power of Shyam = PE / t = 40 x 9.8 x 3/12
= 98 W
Power of Ram > Power of Shyam