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Question
Explain constructive and destructive interference with the help of a diagram?
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Solution
Constructive and destructive interference:
- Points, where the crest of one wave coincides with the crest of another wave and where the trough of one wave coincides with the trough of another wave, are points with the maximum displacement. At these points, displacement is twice that for each wave. These are points of constructive interference.
- Points, where the crest of one wave is coincident with the trough of another, are points with zero displacements. These are points of destructive interference.
Interference for waves
RELATED QUESTIONS
Write the necessary conditions to obtain sustained interference fringes.
Laser light of wavelength 630 nm is incident on a pair of slits which are separated by 1.8 mm. If the screen is kept 80 cm away from the two slits, calculate:
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Answer in brief:
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A. |
B. |
C. |
D. |
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Show graphically the intensity distribution in a single slit diffraction pattern.
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