Given : F = 30 kgf = 30 x 10 N = 300 N, d = 500 m
For coolie A, work done W_{1 } = F x d = 300 x 500 = 150,000 J.
Time t_{1 }= 5 minute = 5 x 60s = 300s
∴ Power developed by P_{1 }= W_{1}/t_{1 } = 150,000/300 = 500 Js^{-1 }
For coolie B, work done W_{2 }= F x d = 3000 x 500 = 150,000 J
Time t_{2 }= 10 minutes = 10 x 60s = 600s
∴ Power developed by P_{2 }= W_{2}/t_{2} = 150,000/600 = 250 Js-^{1 }
(i) W_{1}/W_{2 }= 150,000/150,000 = 1/1.
(ii) P_{1}/P_{2 }= 500/250 = 1/2.