Consider two wires X and Y. The radius of wire X is 3 times the radius of Y. If they are stretched by the same load then the stress on Y is

Options

A. equal to that on X
B. thrice that on X
C. nine times that on X
D. Half that on X

Answer

C

Explanation

`(S_X)/(S_Y)=((r_2)^(2))/((3r_2)^(2))`
`(S_X)/(S_Y)=(1)/(9)`
`S_(Y)=9S_(X)`