Question

Find the volume density of elastic energy of fresh water at a depth of 1000 m

• A. 2.5 kJm^-3
• B. 25 kJm^-3
• C. 0.25 kJm^-3
• D. None

Answer 1

Answer: (B)

25 kJm^-3

Answer 2

$\frac{dW}{V} = \frac{1}{2}P\frac{\Delta V}{V} = \frac{1}{2}P\left( \frac{P}{B} \right)$

= $\frac{(\rho gh)^{2}}{2 \times 2 \times 10^{9}} = \frac{\left( 10^{3} \times 10 \times 10^{3} \right)^{2}}{2 \times 2 \times 10^{9}} = 2.5 \times 10^{4}J/m^{3}$.