What happens if two sound waves having the same frequency interfere in phase?
a) the amplitude of the resultant wave is less than the amplitude of the two individual waves.

b) the amplitude of the resultant wave is greater than the amplitude of either of the two individual waves.

c) the amplitude of the resultant wave is equal to the mean of the amplitudes of the two individual waves.

d) the amplitude of the resultant wave is equal to the amplitudes of the two individual

The correct answer is Option B.

Explanation:

There are two ways by which two waves can interact:

1. Constructive interference: This interference occurs when two waves interact in the same phase. There is always an increase in the amplitude. The amplitude of the resultant wave is always greater than the amplitude of the individual waves.

2. Destructive interference: This interference occurs when two waves does interact in the same phase or interact in the different phase. There is always a decrease in the amplitude. The amplitude of the resultant wave is always less  than the amplitude of the individual waves.

From the above information, it is clear that the answer to this question is Option B.

c. magnitude and direction