JEE Mains · Physics · STD 11 - System of particles and rotational motion
- JEE Mains 2019
- Hard
- MCQ
An \(L-\) shaped object, made of thin rods of uniform mass density, is suspended with a string as shown in figure. If \(AB = BC\), and the angle made by \(AB\) with downward vertical is \(\theta\) then

Pick an option to check your answer.
Answer & Solution
Correct Answer
(B) \(\tan \,\theta = \frac{1}{3}\)
Step-by-step Solution
Detailed explanation
Lets considered mass of each rod is m for stable equilibrium the torque about point \(O\) should be zero. Torque balance about \(O\)
\(\begin{array}{l}
mg\frac{a}{2}\sin \theta = mg\left( {\frac{a}{2}\cos \theta - a\sin \theta } \right)\\
\tan \theta = \frac{1}{3}\\
\Rightarrow {\tan ^{ - 1}}\left( {\frac{1}{3}} \right)
\end{array}\)
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