Young's moduli of two wires A and B are in the ratio 7 : 4 . Wire A is 2 m long and has radius R . Wire B is 1.5 m long and has radius 2 m m . If the two wires stretch by the same length for a gi

Question

Young's moduli of two wires A and B are in the ratio 7 : 4 . Wire A is 2 m long and has radius R . Wire B is 1.5 m long and has radius 2 m m . If the two wires stretch by the same length for a given load, the value of R is close to:

TestHub · Accepted Answer

Strain = ∆ l / l Stress = F / A Young’s modulus = S t r e s s S t r a i n = F / A ∆ l / l = F A l ∆ l Y A Y B = l A A A A B l B = 7 4 2 π r A 2 π r B 2 1.5 = 7 4 r A 2 = 2 1.5 × 7 × 2 m m 2 r A = 1.7 m m

Physics - Elasticity Question with Solution | TestHub

Options:

Doubts & Discussion