Question

A labourer whose own mass is 50kg, carries a load of another 60kg on his head to the top of a building 15 m high. Find the work done by him. (Take g = 10 m/s2)

Answer 1

work done = mass carried X displacement X gravity=60 X 15 X10=9000 Joules

Answer 2

Answer:

total mass = 50 +60 =110 kg

s=15

work done =0

because force and displacement are perpendicular to each other.