Question

When a pressure of 100 atmosphere is applied on a spherical ball of rubber, then its volume reduces to 0.01%. The bulk modulus of the material of the rubber in dyne/cm² is

• A. $10 \times 10^{12}$
• B. $100 \times 10^{12}$
• C. $1 \times 10^{12}$
• D. $20 \times 10^{12}$

Answer 1

Answer: (C)

$1 \times 10^{12}$

Answer 2

1 atm $= 10^{5}N/m^{2}$

$\mathbf{\therefore 100atm = 1}\mathbf{0}^{\mathbf{7}}\mathbf{N/}\mathbf{m}^{\mathbf{2}}$ and $\Delta V = 0.01\% V$

∴ $\frac{\Delta V}{V} = 0.0001$

$K = \frac{P}{\Delta V/V} = \frac{10^{7}}{0.0001} = 1 \times 10^{11}N/m^{2} = 1 \times 10^{12}\frac{Dyne}{cm^{2}}$.