MCQ
With what minimum acceleration can a fireman slides down a rope while breaking strength of the rope is $\frac{2}{3}$ of his weight
- A$\frac{2}{3}g$
- B$g$
- ✓$\frac{1}{3}g$
- DZero
✓
Answer
Correct option: C.
$\frac{1}{3}g$
c
(c) If man slides down with some acceleration then its apparent weight decreases. For critical condition rope can bear only $2/3$ of his weight.
(c) If man slides down with some acceleration then its apparent weight decreases. For critical condition rope can bear only $2/3$ of his weight.
If $a$ is the minimum acceleration then,
Tension in the rope $ = m(g - a)$ = Breaking strength
$⇒$ $m(g - a) = \frac{2}{3}mg$
$⇒$ $a = g - \frac{{2g}}{3} = \frac{g}{3}$
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