A stress of `3.18 xx 10^(8) Nm^(-2)` is applied to a steel rod of length 1m along its length, its Young's modulus is `2 xx 10^(11) Nm^(-2)`. Then the elongation produced in the rod (in mm) is

Options

A. 3.18
B. 6.36
C. 5.18
D. 1.59

Answer

d

Explanation

Young's modulus, `Y = (FL)/(A Delta I) implies Delta I = (FL)/(AY)`
`Delta I = (3.18 xx 10^(8) xx 1)/(2 xx 10^(11))`
`= 1.59 xx 10^(-3) m = 1.59 mm`