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