Question

mention the expression for young's modulus in terms of radius

Answer 1

$E= \frac{Stress}{Strain}=\frac{F/A}{L^{'}/L_0} = \frac{FL_0}{AL^'}$

E is the Young's modulus (modulus of elasticity)

F is the force exerted on an object under tension;

A is the actual cross-sectional area, which equals the area of the cross-section perpendicular to the applied force;

$L^'$ is the amount by which the length of the object changes ($L^'$ is positive if the material is stretched , and negative when the material is compressed);

$L_{0}$ is the original length of the object.

Also, A = $\pi r^2$ , where radius

∴$E = \frac{FL_0}{\pi r^2 L^'}$