A person of mass 60 kg wants to lose 5 kg by goingup and down a 10 m high stairs. Assume he burns twice as much fat while going up than coming down. If 1 kg of fat is burnt on expending 7000 kilocalories, how many times must he go up and down to reduce his weight by 5 kg? Work done in moving up = mgh Work done in moving down =(mgh)/(2) Total work done =(3)/(2) mgh = (3)/(2) xx 60xx 10xx10 N number of trips

A person of mass 60 kg wants to lose 5 kg by goingup and down a 10 m h

1.	A person of mass 60 kg wants to lose 5 kg by goingup and down a 10 m high stairs. Assume he burns twice as much fat while going up than coming down. If 1 kg of fat is burnt on expending 7000 kilocalories, how many times must he go up and down to reduce his weight by 5 kg? Work done in moving up = mgh Work done in moving down =(mgh)/(2) Total work done =(3)/(2) mgh = (3)/(2) xx 60xx 10xx10 N number of trips
Answer» SOLUTION :`5xx7000 XX 10^(3) xx4.2J = 60xx15 xx 10 xx N` `N =(21xx 7xx10^(6))/( 9000)= (147)/(9)xx 10^(3) =16.3 xx 10^(3)` times