Question

With what minimum acceleration can a fireman slide down a rope whose breaking strength is $\frac{2}{3}$ of his weight?
(Hint:-Use the concept of pseudo-force.)

• A. $\frac{2g}{3}$
• B. $g$
• C. $\frac{g}{3}$
• D. $\text{zero}$

Answer 1

The correct option is C $\frac{g}{3}$

Taking the frame of reference on the person sliding, a pseudo-force will be acting on the fireman in the upward direction.
Let $T$ be the tension in the rope.
Since maximum strength of rope is 2/3 of weight,
$\therefore T=\frac{2}{3}mg$
$\Rightarrow T+ma=mg\Rightarrow \frac{2}{3}mg+ma=mg\Rightarrow a=\frac{g}{3}$