Question

A sound wave strikes the reflecting surface at an angle of 70°. The angle between the incident sound wave and reflected sound wave is:

Answer 1

Reflection of sound also follows the law similar to law of reflection of light.

i.e Angle at which sound strikes a reflecting surface = Angle of reflection

So, as the sound wave strucks at 70° it will reflect by 70° opposite to the principle axis.

Therefore the angle between the incident wave and reflected wave will be (70+70)° = 140°.

The attached image will give clear explaination.

Answer 2

Hi there !!

According to Law of reflection of sound :

Angle of reflection = Angle of incidence

Angle of incidence = 70°

Angle between the incident sound wave and reflected sound wave = 70 + 70 = 140 °