Two wires are made of the same material and has the same volume. However wire 1 has cross-sectional area A and wire 2 has cross-sectional area 3A. If the length of wire 1 increases by ax on applying force F, how much force is needed to stretch wire 2 by the same amount ?

Two wires are made of the same material and has the same volume. Howev

1.	Two wires are made of the same material and has the same volume. However wire 1 has cross-sectional area A and wire 2 has cross-sectional area 3A. If the length of wire 1 increases by ax on applying force F, how much force is needed to stretch wire 2 by the same amount ?
Answer» 4F 6F 9F F Solution :Two wire will have some VALUE of Young.s modulus Y Also as volume remains same, so wire of area of crosssection will have length r/3 For wire 1, `Y=(FL)/(ADeltaX)` ..(1) For wire 2 `Y=(F_(l)xxl/3)/(3ADeltax)` …(2) From 1 and 2 `(Fl)/(ADeltax)=(F^(l)l)/(9ADeltax)` `F_(1)=9F` So Correct choice is (C).

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Two wires are made of the same material and has the same volume. However wire 1 has cross-sectional area A and wire 2 has cross-sectional area 3A. If the length of wire 1 increases by ax on applying force F, how much force is needed to stretch wire 2 by the same amount ?

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