Concepts Of Physics MCQ Edition [Volume 1]PhysicsSound Waves
When two waves having the same frequency and a constant phase difference interfere,
Options
- Aenergy is redistributed, and this distribution varies with time
- Benergy is redistributed, and this distribution remains constant in time
- Cthere is an overall gain of energy
- Dthere is an overall loss of energy
Correct answer
B. energy is redistributed, and this distribution remains constant in time
Step-by-step solution
When two coherent waves (same frequency and constant phase difference) interfere, the resultant intensity at any point is given by I = I₁ + I₂ + 2 I₁ I₂ . Since the phase difference is constant in time, the intensity I at any given point in space remains constant with time. The energy is redistributed in space, forming regions of maximum intensity (constructive interference) and minimum intensity (destructive interference). The total energy of the system remains conserved, meaning there is no overall gain or loss o