When tension is applied to a metal wire of length L , it stretches by Δ L . If the same tension is applied to a metal wire of the same material with the same cross-sectional area but of length 2 L , by how much will it stretch?

The metal wire will stretch by

Explanation:

......................................(1)

Where T = Tension applied

ΔL = Extension

L = length

k = constant

T₁ = T₂ = T

A₁ = A₂ =A

L₁ = L

L₂ = 2L

(ΔL)₁ = ΔL

(ΔL)₂ = ?

From equation (1)

.....................(2)

Divide (4) by (3)

wavelength divides in half and speed stays the same.