What is the time interval between the incident sound and the reflected sound for hearing a distinct echo ?

What is the cause of an echo? What is the minimum distance of the obstacle from the source of sound for hearing distinct echo?

Speed OF sound and reflection OF sound

In an experiment to determine the speed of sound, a student stands 150 m from a wall and claps. When he claps once, what is the time interval between the sound of the clap and its echo heard by the student, in terms of v, the speed of sound?

What is the minimum distance of the obstacle from the source of sound for hearing distinct echo ?

The conditions for hearing sound are

The minimum distance between source of sound and reflection surface for the clear hearing of sound is

What is reflection of sound ?

What is the minimum distance between the reflector and the listener to hear the echo, when the speed of sound in air is 330 ms^(-1) ?

What is the difference between the laws of reflection of sound waves and those of light waves ?

What name is given to the repettion of sound caused by the reflection of sound waves?