If the stress on a wire is 107Nm‾² and the wire is stretched from its original length of 10.00 cm to 10.05 cm. The young’s modulus of the wire is?

A. 5.0 x 10⁻⁴ Nm⁻²
B. 5.0 x 10⁻⁵ Nm⁻²
C. 2.0 x 10⁻⁸ Nm⁻²
D. 2.0 x 10⁹ Nm⁻²

Correct Answer:

Option D = 2.0 x 10⁹ Nm⁻²

Explanation

Young’s modulus = ^stress/_strain
strain = ^e/_l=^0.05/₁₀=¹⁰⁷/_0.005
2 x 10⁹Nm⁻²