Question

If two waves of same frequency and same amplitude, on
superposition, produce a resultant disturbance of the same
amplitude, the wave differ in phase by
(a) π (b) 2 π/3
(c) Zero (d) π/3

Answer 1

Answer:

b) 2π/3

Explanation:

Resultant amplitude due to superposition of two waves with phase difference ϕ is given by

A

2

=A

1

2

+A

2

2

+2A

1

A

2

cosϕ

It is given that A

1

=A

2

=A

Thus A

2

=A

2

+A

2

+2A

2

cosϕ

⟹cosϕ=−

2

1

⟹ϕ=

3

2π