Question

Take, bulk modulus of water $B=2100MPa$ . What increase in pressure is required to decrease the volume of $200$ litres of water by $0.004$ percent?

• A. $210\text{kPa}$
• B. $840\text{kPa}$
• C. $8400\text{kPa}$
• D. $84\text{kPa}$

Answer 1

Answer: (D)

Given,
Bulk modulus of water $B=2100MPa$
$=2100\times 10^{6}Pa$
We know that,
$\Delta P=B\left(\frac{-\Delta V}{V}\right)$
Here, $\frac{\Delta V}{V}\times 100$
$\frac{\Delta V}{V}=\frac{0.004}{100}$
$\Delta P=2100\times {\left(10\right)}^6\times \left(\frac{0.004}{100}\right)$
$=\frac{2100\times 10^6\times 4}{1000\times 100}$
$=\frac{8400\times 10^6}{10^5}$
$=84000Pa$
$=84kPa$