Question

A steel wire and a copper wire of equal length and equal cross- sectional area are joined end to end and the combination is subjected to a tension. Find the ratio of copper/steel (a) the stresses developed . In the two wires, (b) the strains developed. (Y of steel = 2xx10^(11) N//m^(2))

Answer 1

Answer is x = 13

Explanation:

Young's modulus, Y = stress/ strain where stress is = F/A

As both wires have same cross sectional area (A) and same tension F, so stress will be equal for both the wires.

Strain ∝ 1/ y

Thus,  strain /stress = Y (copper)/ Y (steel) = 1.3 x 10^11/ 2x 10^11 = 13/20

x = 13