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Question
A wire is suspended from the ceiling and stretched under the action of a weight F suspended from its other end. The force exerted by the ceiling on it is equal and opposite to the weight.
- Tensile stress at any cross section A of the wire is F/A.
- Tensile stress at any cross section is zero.
- Tensile stress at any cross section A of the wire is 2F/A.
- Tension at any cross section A of the wire is F.
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Solution
a and d
Explanation:
According to the diagram, a wire is stretched under the j action of a weight F suspended from its other end.
Clearly, the force at each cross-section is F.
Now applying the formula,
Tensile stress = Force applied/Area of cross-section = F/A
Tension = Applied force = F
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