Answer:
Increasing the air temperature.
Explanation:
As we know that speed of the sound given as
[tex]V=\sqrt{\dfrac{\gamma RT}{M}}[/tex]
Where
R=Gas constant
M=Molecular weight of the gas
T=Temperature ( In Kelvin unit)
V=Speed
γ =Adiabatic gas constant
Form above equation we can say that,velocity of the sound is directly proportional to the temperature .
[tex]V\alpha \sqrt{ T}[/tex]
Therefore we can say that when temperature increase then speed of the sound in air will increase.
