JEE Mains · Physics · STD 11 - System of particles and rotational motion
- JEE Mains 2020
- Hard
- Numerical
Shown in the figure is rigid and uniform one meter long rod \(AB\) held in horizontal position by two strings tied to its ends and attached to the ceiling. The rod is of mass \('m'\) and has another weight of mass \(2m\) hung at a distance of \(75\, cm\) from \(A\). The tension in the string at \(A\) is\(....mg\)

Pick an option to check your answer.
Answer & Solution
Correct Answer
(D) \(1\)
Step-by-step Solution
Detailed explanation
\(\tau_{ B }=0\) (torque about point \(B\) is zero \()\)
\(\left(T_{A}\right) \times 100-(m g) \times 50-(2 m g) \times 25=0\)
\(100 T _{ A }=100 mg\)
\(T_{A}=1 mg\)
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