A thick rope of rubber of density 1.5 kg//m^(3) and Y = 5 xx 10^(6) Nm^(-2) 8 metres in length when hung vertically will increase in length by : (g = 10 ms^(-2))

A thick rope of rubber of density 1.5 kg//m^(3) and Y = 5 xx 10^(6) Nm

1.	A thick rope of rubber of density 1.5 kg//m^(3) and Y = 5 xx 10^(6) Nm^(-2) 8 metres in length when hung vertically will increase in length by : (g = 10 ms^(-2))
Answer» `9.6 xx 10^(-5)` m 9.6 m `19.2xx10^(-3)m` `19.2xx10^(-5)m` Solution :As the WEIGHT of wire is at centre of gravity. `therefore` Only HALF the length ofrope gets extended. `Y=F/A.((L//2))/(Deltal)` `thereforeDeltal=(Mg)/(AY).L/2=(ALpg.h)/(2Ay)=(L^(2)pg)/(2Y)` `=(64xx1.5xx10)/(2xx5xx10^(6))=9.6xx10^(-5)m` So, the CORRECT choice is (a).

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A thick rope of rubber of density 1.5 kg//m^(3) and Y = 5 xx 10^(6) Nm^(-2) 8 metres in length when hung vertically will increase in length by : (g = 10 ms^(-2))

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