Q10 of 29 Page 68

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.


The tensile stress at the cross – section of an object is defined as the ratio of the force (perpendicular to the cross – section) to the area of cross – section.


Here, Tensile stress = F/A


Tension at any cross – section will be Tensile stress x Area of cross – section = F.


Thus, option (a) and (d) are correct.

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