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Question
The bulk modulus and the density of water are greater than those of air. With this much of information, we can say that velocity of sound in air
Options
is larger than its value in water
is smaller than its value in water
is equal to its value in water
cannot be compared with its value in water.
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Solution
cannot be compared with its value in water.
If B is the bulk modulus and ρ is the density, then the velocity of sound is given by:
\[Velocity = \sqrt{\frac{B}{\rho}}\]
If both B and ρ are greater, then we cannot compare \[\frac{2B}{2\rho} = \frac{3B}{3\rho} = \frac{B}{\rho}\]
For proper comparison, we need numerical values.
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