Advertisements
Advertisements
Question
How are we able to see nearby and also the distant objects clearly?
Advertisements
Solution
Eyes have the ability to adjust its focal length which is known as the power of accommodation and we can see nearby and also the distant objects clearly. Relaxation of muscles makes the lens thinner and its focal length increases to make us see the distant objects clearly. The contraction of ciliary muscles increases the curvature of the eye lens and makes the eye lens thicker. Consequently, the focal length of the eye lens decreases. This enables us to see nearby objects clearly.
APPEARS IN
RELATED QUESTIONS
The change in focal length of an eye lens is caused by the action of the ______.
Write the name.
The sensation on the retina persists for a while is
Write the name.
The persons which are unable to distinguish between different colours
Identify and explain concepts given in this diagram.

The eyes of the nocturnal birds like owls are having a large cornea and a large pupil. How does it help them?
The 'eye muscles' are controlled by which cranial nerves?
Having two eyes facilitates in
A: Increasing the field of view
B: Bringing three-dimensional view
C: Developing the concept of distance/size
Then the correct option is/are
Near and far points of a young person normal eye respectively are:
The least distance of distinct vision for a normal eye is ____________.
The danger signals installed at the top of tall buildings are red in colour. These can be easily seen from a distance because among all other colours, the red light
In simple microscope ______ lens is used.
Adjusting the focal length of the eye lens to view objects at different distances is done by ______.
Give the reason for the following:
A person from bright sunlight outside enters a poorly lit room and feels blinded for a short while.
Name the following:
Two types of adaptations.
Define the following term:
Adaptation
The figures (A) and (B) given below are showing some kind of adjustment. Study the figures and answer the questions that follow.
| A | ![]() |
![]() |
B |
- Identify the kinds of adjustments done in the figures (A) and (B).
- Distinguish between the adjustments of figures (A) and (B) on the basis of:
- The size of pupil.
- The pigment which gets regenerated.
- Cells of the retina.


