If temperature varies linearly with height near the earth’s surface.Temperature at the surface of earth is T₁&T₂ at a height h above the surface,calculate time’t’ when asound wave is produced at a height’x’.velocity of sound at earth’s surface is ‘c’.

Velocity (dx/dt) of longitudinal wave is directly proportionbal to the underroot of temperature.
Consider the temperature gradient (Tx = Ti + (Ti – Tf .x/L))at any length ‘x’ from one end.
Heat flows from highr temperature to lower temperature.
Put the value of Tx in the velocity equation which is the function of ‘x’ and calculate the time.


Good Luck.....