Question

A steel wire of length 20 cm is stretched to increase by 0.2cm.find the lateralc strain in the wire if the poisons ratio for steel outs 0.19

Answer 1

Poisson's Ration (σ) = -ΔD/D / Δl/l 

σ = 0.19 ( Given )

l = 20 cm = 20 x 10 ⁻² m 

Δl = 0.2 cm = 0.2 x 10 ⁻² m 

ΔD/D = - σ x Δ l/l 

ΔD/D = - 0.19 x 0.2 x 10⁻² / 20 x 10⁻²

ΔD/D =  - 0.19 x 0.2 /20

ΔD/D = 0.038/20 

ΔD/D = 0.0019 = 1.9 x 10⁻³ 

Answer 2

Poisson's ratio = lateral strain/longitudinal strain

0.19 = lateral strain/[Δl/l]

lateral strain = 0.19 × (Δl/l]

lateral strain = 0.19 × (0.2/20)

lateral strain = 0.19 × 1/100

lateral strain = 0.0019

Hope it helps..!