Question

A mass $M$ is hung with a light inextensible string. Tension in horizontal part of string is:

• A. $\sqrt{3}Mg$
• B. $\sqrt{2}Mg$
• C. $\frac{Mg}{\sqrt{3}}$
• D. $\frac{Mg}{2}$

Answer 1

The correct option is A $\sqrt{3}Mg$

Let $T_1$ be the tension of horizontal part of string.

From FBD, $T_2\sin 30=Mg\Rightarrow T_2=2Mg$

and $T_1=T_{2}cos30=2Mg\times \frac{\sqrt{3}}{2}=\sqrt{3}Mg$