MCQ
The decrease in the potential energy of a ball of mass $20 \,kg$ which falls from a height of $50 \,cm$ is ............ $\mathrm{J}$
- A$968$
- ✓$98$
- C$1980$
- DNone of these
✓
Answer
Correct option: B.
$98$
b
(b)$\Delta U = mgh = 20 \times 9.8 \times 0.5 = 98\,J$
(b)$\Delta U = mgh = 20 \times 9.8 \times 0.5 = 98\,J$
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