Question

As the velocity of the sound source approaches the speed of sound, the wave fronts ahead of the object begin to appear as
a) separately distinguishable waves
b) single wave front
c) cylindrical
d) a cone shaped shock wave
and when the velocity of the sound source exceeds the speed of sound, the wave fronts form
a) separately distinguishable waves
b) single wave front
c) cylindrical
d) a cone shaped shock wave

Answer 1

take a look at this link:
http://physics.info/shock/