MCQ
A boy whose mass is $50\,kg$ stands on a spring balance inside a lift. The lift starts to ascent with an acceleration of $2\,m{s^{ - 2}}.$ The reading of the machine or balance $(g = 10\,m{s^{ - 2 }})$ is ........ $kg$
- A$50$
- B$0$
- C$49$
- ✓$60$
✓
Answer
Correct option: D.
$60$
d
(d) $R = m\,(g + a) = 50 \times \,(10 + 2) = 600\,N = 60\,kg\,wt$
(d) $R = m\,(g + a) = 50 \times \,(10 + 2) = 600\,N = 60\,kg\,wt$
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