Question

If the bulk modulus of water is 2100 MPa, what is the speed of in water?

• A. 1450 m s–1
• B. 2100 m s–1
• C. 1400 m s–1
• D. 1200 m s–1

Answer 1

Answer: (A)

1450 m s–1

Answer 2

Speed of sound in water is

$v = \sqrt{\frac{B}{\rho}} = \sqrt{\frac{2100 \times 10^{6}}{10^{3}}} = 1450ms^{- 1}$

Where B is the bulk modulus and $\rho$is the density of water.

Here, $B = 2100MPa = 2100 \times 10^{6}Pa$

$\rho = 10^{3}kgm^{- 3}$

$\therefore v = \sqrt{\frac{2100 \times 10^{6}}{10^{3}}} = 1450ms^{- 1}$