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Question
Write two points of difference between the phenomena of interference and diffraction.
Solution
| Interference | Diffraction | |
| 1 | Interference is the phenomenon of waves where waves from two different coherent sources superimpose at a given point and creates fringes. |
The phenomenon of bending of light around the corners of an opaque object which obstructs the path of light is called diffraction. |
| 2 | In interference pattern the intensity of dark fringe is completely zero. | In diffraction pattern the intensity of secondary minima is minimum, but not completely zero. |
| 3 | In interference pattern the width of all the interference fringes is equal. | In diffraction pattern the width of central maxima is large, and on increasing distance, the width of maxima decreases. |
| 4 | In interference pattern the intensity of all the bright bands is equal. | In diffraction pattern the intensity of all the secondary maxima is not equal. |
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