Question

Define interference. Mention the condition for constructive and destructive interference. 
 

Hint:

For constructive interference, the phase difference must be an integer multiple of \( 2\pi \), and for destructive interference, it must be an odd multiple of \( \pi \).

Answer 1

- Interference: Interference is the phenomenon in which two or more waves superpose to form a resultant wave. This effect occurs when the waves meet in such a way that they combine to form either a stronger or weaker wave. - Condition for Constructive Interference: When two waves meet such that their displacements are in the same direction, the resultant amplitude is the sum of the amplitudes of the two waves. The condition for constructive interference is: \[ \Delta \phi = 2n\pi \quad (n = 0, 1, 2, \dots) \] where \( \Delta \phi \) is the phase difference between the two waves. - Condition for Destructive Interference: When the displacements of the two waves are in opposite directions, the resultant amplitude is the difference of the two amplitudes. The condition for destructive interference is: \[ \Delta \phi = (2n+1)\pi \quad (n = 0, 1, 2, \dots) \]