The adjacent graph shows the estension `(Deltal)` of a wire of length 1m suspended from the top of a roof at one end and with a load W connected to the other end. If the cross-sectional area of the wire is `10^-6m^2`, calculate the Young's modulus of the material of the wire.

Options

A. `2 xx 10^11 N//m^2`
B. `2 xx 10^-11 N//m^2`
C. `3 xx 10^-12 N//m^2`
D. `2 xx 10^-13 N//m^2`

Answer

A

Explanation

From the length `l = 10^-4 m, F = 20 N, A = 10^-6 m^2`
`L = 1 m`
`:. Y = (FL)/(A l)`
=`(20 xx 1)/(10^-6 xx 10^-4)`
=`20 xx 10^10 = 2 xx 10^11 N//m^2`.