Question

A string of negligible mass going over a clamped pulley of mass $m$ supports a block of mass $M$ as shown in the figure. The force on the pulley by the clamp is given by (Take acceleration due to gravity$=g$)

• A. $\sqrt{2}Mg$
• B. $\sqrt{2}mg$
• C. $\left(\sqrt{(M+m{)}^2+m^2}\right)g$
• D. $\left(\sqrt{(M+m{)}^2+M^2}\right)g$

Answer 1

The correct option is D $\left(\sqrt{(M+m{)}^2+M^2}\right)g$

In order to be in equilibrium:

$F_{clamp}cos\theta =Mg$

$F_{clamp}sin\theta =(M+m)g$

$F_{net}=g\sqrt{M^2+(m+M{)}^2}$