Q.15.4 (a) Use the formula to explain why the speed of sound in air
(a) is independent of pressure,
Where are the Bulk's modulus and the density respectively
As we know
where M is molecular weight of air and V is the volume of 1 mole of air
From the ideal gas equation PV=nRT
since we are talking about 1 mole we take n = 1
PV=RT
The expression for the speed of sound becomes
, M and R are constant therefore at constant Temperature the speed of sound in the air do not change and it is clear that speed is independent of velocity.