Copper of fixed volume `V` is drawn into wire of length l. When this wire is subjected to a constant force F, the extension produced in the wire is `trianglel`. Which of the following graphs is a straight line?

Options

A. `Delta l` versus `(1)/(l)`
B. `Delta l` versus `l^(2)`
C. `Delta l` versus `(1)/(l^(2))`
D. `Delta l` versus `l`

Answer

b

Explanation

For Hooke's law, young Modulus
`Y = (F//A)/(Delta I//I) = (F xx I)/(Delta I xx A)`
`V = A xx I` = constant
From Eqs. (i) and (ii)
`Y = (F xx I xx I)/(V)` and `Delta I = (F)/(V xx Y) I^(2) implies Delta I prop I^(2)`