If any explosion takes place at the bottom of a lake, what type of shock waves in water will take place?

A girl is sitting in the middle of a park of dimension 12 m × 12 m. On the left side of it there is a building adjoining the park and on right side of the park, there is a road adjoining the park. A sound is produced on the road by a cracker. Is it possible for the girl to hear the echo of this sound? Explain your answer.

Why do we hear the sound produced by the humming bees while the sound of vibrations of pendulum is not heard?

Sound produced by a thunderstorm is heard 10 s after the lightning is seen. Calculate the approximate distance of the thunder cloud. (Given speed of sound = 340 m s^-1)

For hearing the loudest ticking sound heard by the ear, find the angle x in the Fig.12.4.