MCQ
A plane wave front falls on a convex lens. The emergent wave front is:
- APlane
- BCylindrical
- CSpherical diverging
- DSpherical converging
✓
Answer
- Spherical converging
Explanation:
A convex lens is thicker at the middle. When a light ray is incident parallel
to principle axis it is refracted towards the focal point. Similarly when a plane wave front is incident on a convex lens the light is refracted towards a point on the focal plane.
As the light is getting focused at a point it is converging and the emerging wave front is a spherical converging.
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