MCQ
Huygens's concept of secondary wave:
- AAllows us to find the focal length of a thick lens.
- BIs a geometrical method to a find a wavefront.
- CIs used to determine the velocity of light.
- DIs used to explain polarisation.
✓
Answer
- Is a geometrical method to a find a wavefront.
Explanation:
Huygens principle states that "Every point on a wave-front may be considered a source of secondary spherical wavelets which spread out in the forward direction at the speed of light. The new wave-front is the tangential surface to all of these secondary wavelets."
Thus it is geometrical method to find the wavefront.
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