JEE Mains · Physics · STD 11 - 6. system of particles and rotational motion
An object of mass 8 kg is hanging from one end of a uniform rod \(C D\) of mass 2 kg and length 1 m pivoted at its end \(C\) on a vertical wall as shown in figure. It is supported by a cable \(A B\) such that the system is in equilibrium. The tension in the cable is:
(Take \(g=10 m s ^{-2}\) )
- A 240 N
- B 90 N
- C 300 N
- D 30 N
Answer & Solution
Correct Answer
(C) 300 N
Step-by-step Solution
Detailed explanation
Taking torque about point C \(\frac{\text T}{2} \times 60=20 \times 50+80 \times 100\) \(\Rightarrow 3 \text T=100+800\) \(\Rightarrow=300\text N\)
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