Question

Calculate the force required to produce an extension of 2 mm in stell wire of length 3m and diameter 1mm ( young's modulus the material is 2×10^11n/m^2)

Answer 1

Answer:

Force required = 1.04 x $10^{2}$ N

Explanation:

Area of wire = π $r^{2}$ = π x 0.25 x $10^{-6}$ $m^{2}$

Young's modulus = Stress / Strain

$Y = \frac{F /A}{l'/L}$    let l' be the change in length

$F = \frac{Y A l'}{L}$

   = 2 x $10^{11}$ x 0.25 x 3.14 x $10^{-6}$ x 2 x $10^{-3}$ / 3

   = 1.04 x $10^{2}$ N