Question

With what minimum acceleration can a fireman slide down a rope while breaking strength of the rope is $\frac{2}{3}$ of his weight

• A.
• B.
• C.
• D.

Answer 1

The correct option is C

If man slides down with some acceleration then its apparent weight decreases. For critical condition rope can bear only $\frac{2}{3}$ of his weight. If a is the minimum acceleration then,
Tension in the rope = m(g - a) = Breaking strength
$\Rightarrow m(g-a)=\frac{2}{3}mg\Rightarrow a=g-\frac{2g}{3}=\frac{g}{3}$