Question

One end of massless rope, which passes over a massless and frictionless pulley P is tied to a hook C while the other end is free. Maximum vertical force that the clamp can bear is 180 N. With what value of minimum safe acceleration (in ${ms}^{-2}$) can a man of 60 kg climb down the rope ?

• A. 10
• B. 5
• C. 8
• D. 4

Answer 1

Answer: (D)

4

If monkey move downward with acceleration a then its apparent eight deceases$.$

In that condition tension in string $m(g-a)$ this should not be exceed over breaking strength of the rope $i.e.,$

$\begin{array}{c}360\ge m\left(g-a\right)\\ 360\ge 60\left(10-a\right)\\ 360\ge 600-60a\\ 60a\ge 600-360\\ 60a\ge 240\\ a\ge 4m/s^2\end{array}$

Hence,

option $\left(D\right)$ is correct answer.