Question

. The wire of length L is acted upon a pulling force and hence its length is increased by dL
If wire length is doubled (2L), what should be changed to produce same deformation for
same applied force?​

Answer 1

I don't known sorry plz

Answer 2

Given:

Length of wire = L

Increased length = dL

To find:

The change to be made to produce same deformation if length is made 2L.

Solution:

We know that, Young's modulus Y = F*L/ A*ΔL

Where F = force applied,

A = Cross-sectional area of the wire

Here ΔL = dL

∴ Y = F*L/ A*dL

dl = F*L/ A*Y

dl ∝ L/A

If dl needs to remain the same, when the length is doubled then Area need to be also made double as Y is a constant and F also remains the same.

Therefore cross-sectional area of the wire should be doubled.