MCQ
A barometer kept in a stationary elevator reads $76 cm$. If the elevator starts accelerating up the reading will be
- AZero
- BEqual to $76 cm$
- CMore than $76 cm$
- ✓Less than $76 cm$
✓
Answer
Correct option: D.
Less than $76 cm$
d
(d) $h = \frac{P}{{\rho g}}$
(d) $h = \frac{P}{{\rho g}}$
$h \propto \frac{1}{g}$. If lift moves upward with some acceleration then effective g increases. So the value of h decreases i.e. reading will be less than $76 cm.$
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