Question

man weighing 80 kg has to carry a box of 50 kg from ground floor to the fourth floor which is at a height of 90 metres. Calculate the work done by the man against gravity.​

Answer 1

Answer:-

Potential energy=mass×acceleration due to gravity x−height

P.E.=m×g×h

According to the given condition -

m=80+20=100kg

g=9.8m/s sq

h=25×40=1000cm=1m

P.E=Work Done=100×9.8×1=980J

Power is rate of work done = Time Taken by Work Done.

=> 980 by 20

=> 49J/s=49Watt