A spring is made of material of Young's modulus `10^(11)N//m^(2)`. When a weight of 10 kg is suspended vertically the elongation produced in the spring is 4 mm. If the load is reduced to half the elongation in the spring will be

Options

A. 1 mm
B. 4 mm
C. 2 mm
D. 0.2 mm

Answer

C

Explanation

`l_(1) prop F_(1), l_(2) prop F_(2)`
`therefore (l_(2))/(l_(1)) =(F_(2))/(F_(1)) =(1)/(2)`
`therefore l_(2)=(1)/(2) xx l_(1)=(4)/(2)=2 mm. `