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 :
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 :
Show Hint
- 0.5 mg
- 2 mg
- 0.75 mg
- 1 mg
The Correct Option is D
Solution and Explanation
Torque about \(B\) = 0: \(T_A\times 1 = mg\times 0.5 + 2mg\times 0.25\).
\(T_A = 0.5\,mg + 0.5\,mg = mg\).
(Check: \(T_B = 3mg - mg = 2mg\).)
Answer: (4) 1 mg
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