Question

A man is riding on a cycle with velocity 7. 2 km per hour up a hill having a slope 1 in 20. The total mass of the man and cycle is 100kg. The power of the man is​

Answer 1

Power of man is equla to change in Potential energy per second.Hence

P=mgvh

wher vh=v/20

is speed of changing the height

vh=1/20*7.2/3.6 m/s=0.1 m/s

Hence power of man =100*9.8*0.1=98W

Answer 2

Answer:98 Watt

Explanation:v=7.2km/hr;7.2*5/18=2m/sec;

Mass=100 kg;

Slope is given = 1 in 20 ; sin theta = 1/20;

When man and cycle moves up then the component of weight that opposes its motion = F= mgsin theta

P=F*v

P=mgsin theta *v

P=100*9.8*(1/20)*2

P=98 Watt

Hint for diagram :: As the man is moving up a hill the daigram should be of inclined plane ..

Thanks hope it helps