Question

If two waves having amplitudes 2A and A and same frequency and velocity, propagate in the same direction in the same phase, the resulting amplitude will be

• A. 3A
• B. $\sqrt{5}A$
• C. $\sqrt{2}A$
• D. A

Answer 1

Answer: (A)

3A

Answer 2

In the same phase φ = 0 so resultant amplitude

= $a_{1} + a_{2} = 2A + A = 3A$