JEE Mains · Physics · STD 11 - 6. system of particles and rotational motion
A heavy iron bar, of weight \(\mathrm{W}\) is having its one end on the ground and the other on the shoulder of a person. The bar makes an angle \(\theta\) with the horizontal. The weight experienced by the person is _______.
- A \(\frac{W}{2}\)
- B \(W\)
- C \(\mathrm{W} \cos \theta\)
- D \(\mathrm{W} \sin \theta\)
Answer & Solution
Correct Answer
(A) \(\frac{W}{2}\)
Step-by-step Solution
Detailed explanation
\(R=\) net reaction force by shoulder Balancing torque about pt of contact on ground: \(\mathrm{W}\left(\frac{\mathrm{L}}{2} \cos \theta\right)=\mathrm{R}(\mathrm{L} \cos \theta)\) \(\Rightarrow \mathrm{R}=\frac{\mathrm{W}}{2}\)
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