Question

A steel wire of 1mm diameter and of length 1m is stretched by applying force of 10N if the increase in length is 0.006mm find the strain​

Answer 1

Explanation:

1. A circular rod of diameter 20 mm and 500mm long is subjected to a tensile force of 45 KN. the modulus of elasticity may be taken as 200 KN/mm2. Find stress, strain and elongation of the bar due to the applied load. [APR/MAY 2011]

Given data:

Load p =45 KN = 45 x 103 N

Young’s modulus E = 200 KN /mm2

Length of the rod, l = 500 mm

Diameter of the rod = 20 mm

Data asked:

Stress, strain, elongation CIRCULAR ROD

Solution:

Cross sectional area; A = πd2/4 =π x 202/4 = 314.159 mm2

Stress σ =load / area =45x103/314.5 = 143. 24 N/mm2

Strain, e = stress / young’s modulus =143.24/200x103 = 0.0007162

Elongation δl=Pl/AE = (45x103 x 500) / (314.159 x 200x103) = 0.358 mm

Result:

Stress σ = 143.24 N/mm2

Strain = 0.0007162

Elongation δl = 0.358 mm