A cubic vessel of height 1 m is full of water. The minimum work done in taking the water out is:
Correct answer: A. 5000 J
- A. 5000 J
- B. 10000 J
- C. 5 J
- D. 10 J
Explanation
Total water volume = 1m × 1m × 1m = 1m3 mass = 1m3 × 1000 kgm-3 = 1000 kg . Height is 1 m, so the center of mass will be at a distance of 0.5 m from the ground. potential energy = mgh = 1000 x 10 x 0.5 = 5000 J
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