Question 17
Light emerges out of a convex lens when a source of light kept at its focus. The shape of wavefront of the light is :
Solution
When a point source of light is placed at the focus of a convex lens, the light rays after passing through the lens become parallel (collimated).
Parallel rays have plane wavefronts — the wavefront is perpendicular to the direction of propagation, and since all rays are parallel, the wavefront is a flat plane.
The correct answer is Option (2): plane.
Create a FREE account and get:
- Free JEE Mains Previous Papers PDF
- Take JEE Mains paper tests
