Question

In the arrangement shown is figure, the ends $P$ and $Q$ of an unstretchable string move downwards with uniform speed $U$. Pulleys $A$ and $B$ are fixed. Mass $M$ moves upwards with a speed.

• A. $2U\cos \theta$
• B. $U\cos \theta$
• C. $\frac{2U}{\cos \theta }$
• D. $\frac{U}{\cos \theta }$

Answer 1

The correct option is D $\frac{U}{\cos \theta }$

Speed of Maas M be let = V

So the speed of Q and P depends on the upward speed of M

$vcos\theta =u$

$v=\frac{u}{cos\theta }$