Two waves of amplitudes 3 m and 2 m, respectively superimpose at a point in the same phase. The resultant amplitude would be
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) → 5 m
By the principle of superposition the displacements add. When the two waves arrive in the same phase, their crests coincide and the resultant amplitude is the sum of the amplitudes.
\( \displaystyle A = \sqrt{a_1^{2} + a_2^{2} + 2a_1 a_2\cos\phi} = a_1 + a_2 \quad (\phi = 0) \)
\( A = 3\,\mathrm{m} + 2\,\mathrm{m} = 5\,\mathrm{m} \)