Question

Light emerges out of a convex lens when a source of light kept at its focus. The shape of wavefront of the light is ______.

Options

• Both spherical and cylindrical

• Cylindrical

• Spherical

• Plane

Answer 1

Light emerges out of a convex lens when a source of light kept at its focus. The shape of wavefront of the light is plane.

Explanation:

A point source at the focus produces spherical wavefronts that diverge toward the lens. The convex lens refracts these rays into a parallel beam, which corresponds to a plane wavefront. Essentially, the lens “flattens” the curvature of the incoming light waves.