#
The temperature at which the speed of sound in air becomes double of its value at 27 degee celsius?
(a)= -123 deg cel

(b)= 927 deg cel

(c)= 327 deg cel

(d)= 54 deg cel

velocity of sound waves v = sqrt (P/rho)

P is the pressure and rho is the density.Write this as

v1 = root(p1/rho)

v2= root (p2/rho)

square both sides

v1^2 = p1 /rho

v2^2 = p2/rho

Take the ration

v1^2/v2^2 = p1/p2

Put the values v1=1 and v2 = 2

YOu get

1/4 = p1/p2

p1 = n kb T1 and p2= n kb T2. Here n is the number density. kb Boltzmann constant and T1 and T2 are temperatures.

If you use it in the above equation you get

T2= 4 T1

T1 is 27 degrees= 273 + 27 = 300

T2= 1200 degrees = 1200-273 = 927 degrees.