Speed of sound wave in the air

1. is independent of temperature

2. increases with the pressure

3. increases with increase in humidity

4. decreases with increase in humidity

(3) Hint: The speed of the sound wave depends on the temperature and the density of the air.
Step 1: Find the dependence of the sound wave on the density of the air.
Due to the presence of moisture density of air decreases.
We Know that the speed of sound in air is given by, v=γPρ
For air γ and P are constants,
                                             ν1ρ,  where ρ is the density of air.
                                              ν2ν1=ρ1ρ2                
where ρ1 is the density of dry air and ρ2 is the density of moist air.
Step 2: Find the comparative speed of the sound in the moist air.
As                                 ρ2<ρ1=ν2ν1>1ν2>ν1       
Hence, the speed of the sound wave in the air increases with an increase in humidity.