Water is drawn from a well in a 5 kg drum of capacity 55 L by two ropes connected to the top of the drum. The linear mass density of each rope is 0.5 kgm−1. The work done in lifting water to the ground from the surface of water in the well 20 m below is [g = 10 ms−2]
1.4×104 J
Work done in lifting water and drum is 60×10×20 J =12000 J
Total mass of ropes =40 × 0.5 kg =20 kg
Work done in the case of ropes is 20 × 10 × 10 = 2000 J
Total work done = 14000 J