A heavy iron bar, of weight 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:
- \(\frac{W}{2}\)
- W
- \(W cos\theta\)
- \(W sin\theta\)
The Correct Option is A
Solution and Explanation
Step 1: Concept of center of mass The weight of the bar is uniformly distributed. Since the bar is uniform, the center of mass lies at the midpoint of the bar.
The total weight \( W \) of the bar is supported by two points:
- One end is on the ground.
- The other end is on the shoulder of the person.
Step 2: Distribution of weight In a symmetric situation like this, the total weight is evenly distributed between the two points of contact.
\[ \text{Weight experienced by the person} = \frac{W}{2}. \]
Final Answer: \( \frac{W}{2} \).
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