Question

If a wire is stretched by 2%, then find the energy
stored in the wire per unit volume (in J/m^3)
(Y= 4 * 10^8 N/m^2)
(1) 4 x 10^4
(2) 8 x 10^4
- (3) 12 * 10^4 (4) 16 × 10^4​

Answer 1

Answer ⇒ Option (b).

Explanation ⇒

Using the formula,

Energy stored by the wire per unit volume = 1/2 × Stress × Strain.

Also, Stress = Young modulus (Y) × Strain.

∴ U = 1/2 × Y × (Strain)²

Now, Strain = (102L/100 - L)/L

∴ Strain = 2/100

∴ U = 1/2 × 4 × 10⁸ × (2/100)²

∴ U = 2 × 10⁸ × 4/10⁴

∴ U = 8 × 10⁴ J/m³

Hence, Option (2). is the correct choice.

Hope it helps.

Answer 2

Answer:

here is your answer.

hope it's helpful....