MCQ
The decrease in the potential energy of a ball of mass 20kg which falls from a height of 50cm is:
- A968J
- B98J
- C1980J
- DNone of these
✓
Answer
- 98J
Explanation:
Decrease in potential energy ΔU = mg(h2−h1)
ΔU = mgh = 20 × 9.8 × 0.5 = 98J
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