Question

the bulk modulus of copper is is 1.4×10¹¹ Pa and the coefficient of linear expansion is 1.7×10^(-5)/(C°).
What hydrostatic pressure is necessary to prevent A copper blocks from expanding when its temperature is increased from 20°C to 30°C?
A] 6.0×10^(5) Pa
B] 7.1×10^(7) Pa
C] 5.2 × 10^(6) Pa
D] 40 atm ​

Answer 1

Dear Student,

● Answer -

(B) 7.1×10^7 Pa

● Explanation -

As we know, Young's modulus is given by -

Youngs modulus = stress / strain

Y = (F/A) / (∆V/V)

As we know, P = F/A and ∆V/V = 3α∆T

Y = P / (3α∆T)

P = Y × 3α × ∆T

Substitute values,

P = 1.4×10^11 × 3 × 1.7×10^-5 × (30-20)

P = 7.14×10^7 Pa

Therefore, pressure necessary is 7.14×10^7 Pa.

Thanks dear. Hope this helps you...