Question 200: Properties of Matter

Question

A wire elongates by $$l$$ $$mm$$ when a LOAD $$W$$ is hanged from it. If the wire goes over a pulley and two weights $$W$$ each are hung at the two ends, the elongation of the wire will be (in $$mm$$)

Accepted Answer

Case $$(i)$$
At equilibrium, $$T=W$$
$$Y = {{W/A} \over {\ell /L}}{\mkern 1mu} {\mkern 1mu} {\mkern 1mu} {\mkern 1mu} {\mkern 1mu} {\mkern 1mu} {\mkern 1mu} {\mkern 1mu} {\mkern 1mu} {\mkern 1mu} {\mkern 1mu} {\mkern 1mu} {\mkern 1mu} {\mkern 1mu} ...\left( 1 ight)$$
Case $$(ii)$$  At equilibrium $$T=W$$
$$	herefore$$ $$Y = {{W/A} \over {{{\ell /2} \over {L/2}}}} \Rightarrow Y = {{W/A} \over {\ell /L}}$$
$$ \Rightarrow $$ Elongation is the same.

Answer

$$l$$

Answer

$$2l$$

Answer

zero

Answer

$$l/2$$

Properties of Matter

A wire elongates by $l mm when a LOAD W is hanged from it. If the wire goes over a pulley and two weights W each are hung at the two ends, the elongation of the wire will be (in mm$)

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