Please solve. 

Asked by kiranbora10 | 2nd Apr, 2020, 12:42: PM

Expert Answer:

A man of mass 80 kg is carries a load of 20 kg upto a height 20 m in 40 s. 
Thus, 
 
Given information - 
 Total mass = 80 + 20 = 100 kg 
h = 20 m 
s = 40 s 
g = 10 m/s2 
 
a) If the person is at ground level then the potential energy at that point is suppose to be zero. 
When man carries load upto a certain height the, 
Potential energy at height of 20 m = Work done = mgh = 100 x 10 x 20 = 20000 J 
 
Thus, change in potential energy = work done by him = 20000 Joules 
 
b) Power = Work done/ time 
 Thus, 
P = 20000/40 = 500 W
Thus power required by man to carry away the load upto 20 m in 40 s was 500 Watt. 

Answered by Shiwani Sawant | 2nd Apr, 2020, 01:49: PM