Question

a boy strikes one end of a long pipe with a stone. another boy who keeps his ear close to the other end of the pipe heard two sounds in a short interval of time. explain, how?

Answer 1

He hears two sounds because:-
1-The reflecting surface of the sound is larger than the wavelength of the sound
2- Due to the reason specified in (1), an echo is produced
3- He hears two sounds, one which travels in air and second which he hears through the solid long pipe.. as a fact he will listen the solid sound first and the air transmitted sound later...
hope it helps

Answer 2

He hears two sounds because:-

1-The reflecting surface of the sound is larger than the wavelength of the sound

2- Due to the reason specified in (1), an echo is produced

3- He hears two sounds, one which travels in air and second which he hears through the solid long pipe.. as a fact he will listen the solid sound first and the air transmitted sound later...

hope it helps.......