Physics
How does the action of the convex lens differ from that of a concave lens on a parallel beam of light incident on them? Draw diagrams to illustrate your answer.
Answer
| Convex Lens | Concave Lens |
|---|---|
| In the case, when a parallel beam of light ray is incident on a convex lens, the prism in the upper part bends the incident ray downwards. | In the case, when a parallel beam of light ray is incident on a concave lens, the upper part of the lens bends the incident ray upwards. |
| The ray incident on the lower part of the prism is bent in upward direction. | The ray incident on the lower part of the prism is bent in downward direction |
| The central part which is a parallel-sided glass slab passes the ray undeviated. | The central part which is a parallel-sided glass slab passes the ray undeviated. |
Convergent action of Convex lens is shown in the below diagram:
Divergent action of Concave lens is shown in the below diagram:
Related Questions
Show by a diagram the refraction of two light rays incident parallel to the principal axis on a convex lens by treating it as a combination of a glass slab and two triangular glass prisms.
Show by a diagram the refraction of two light rays incident parallel to the principal axis on a concave lens by treating it as a combination of a glass slab and two triangular glass prisms.
A ray of light, after refraction through a concave lens emerges parallel to the principal axis.
(a) Draw a ray diagram to show the incident ray and its corresponding emergent ray.
(b) The incident ray when produced meets the principal axis at a point F. Name the point F.
A ray of light, after refraction through a convex lens emerges parallel to the principal axis.
(a) Draw a ray diagram to show it.
(b) The incident ray passes through a point F on the principal axis. Name the point F.