Advertisements
Advertisements
Question
What is a lens?
Solution
A lens is a transparent refracting medium bounded by two curved surfaces which are generally spherical.
APPEARS IN
RELATED QUESTIONS
State the condition when a lens is called an equi-convex or equi-concave.
The diagram below shows a lens as a combination of a glass slab and two prisms.
- Name the lens formed by the combination.
- What is the line XX’ called?
- Complete the path of the incident ray AB after passing through the lens.
- The final emergent ray either meets XX’ at a point or appears to come from a point on XX’. Label it as F. What is this point called?
In the following figure (a) and (b), F1 and F2 are positions of the two foci of thin lenses. Draw the path taken by the light ray AB after it emerges from each lens.
 |
| (a) |
 |
| (b) |
In figure, (a) and (b), F1 and F2 are the two foci of thin lenses and AB is the incident ray. Complete the diagram to show the path of the ray AB after refraction through each lens.
 |
| (a) |
 |
| (b) |
A ray of light after refraction through a lens emerges parallel to the principal axis of the lens. The incident ray either passes through ______.
A ray of light incident on a lens parallel to its principal axis, after refraction passes through or appears to come from ______.
In the diagram below, XX’ represents the principal axis, O the optical centre and F the focus of the lens. Complete the path of rays A and B as they emerge out of the lens.
 |
 |
| (a) | (b) |
Make the correct choices in the following items:
lf the image can be focused on a screen it must be
State the nature and position of the object on the principal axis to obtain a real and magnified image.
Complete the following diagram and state what happens to the ray of light after refraction through the lens.
