[" 6.A man of mass "60kg" lifts a "15kg" mass to the "],[" top of a building of height "10m" in "5" minutes."],[H" is efficiency is "],[[" 1) "10%," 2) "20%," 3) "30%," 4) "40%]]

A man of mass 60kg lifts a 15 kg mass to the top of a building of height 10 m in 5 minutes. H is efficiency is

A man weighing 60 kg. lifts a body of 15 kg. to the top of a building 10 m high in 3barminutes. His efficiency is

A man of mass 60 kg walks up to the top of a building of height 15 m. Calculate the increase in potential energy.

A man of mass 60 kg climbed up 15 steps, each of height 15 cm. Find the work done .

Two persons A and B each of mass 60 kg are carrying loads 15 kg each. If they reach the top of a building of height 10 m in 20s and 40s respectively, the ratio of their efficiencies is