Question

(b) A loaded sack of total mass 100kg falls down from the floor of a lorry 2m high. Calculate the work done by gravity on the load. (take g = 10ms-2)

Answer 1

Explanation:

The work done is the product of force and displacement. Force is the product of mass and acceleration which in this case is acceleration due to gravity. Thus the work done to lift the load is 196J.

Answer 2

Explanation:

mass =100kg ,

height=2m

u= 0m/s

from second equation of motion

v^2-u^2=2as

v^2-(0)^2=2×10×2

v^2=40

we Know that work done =1/2×mass(v^2-u^2)

=1/2×100×(40-0)

=50×40

=2000j

sorry by mistake i forget to apply Zero ok it Is correct.