(Multiple Choice Question)
Ques1.
When a person is myopic, he/ she can clearly see:
(a) both nearby and far off objects
(b) Only nearby objects
(c) only far off objects
(d) Neither nearby nor far off objects
Ques2.
The defect of myopia can be corrected by using:
(a) Concave lens
(b) Convex lens
(c) Either concave or convex
(d) A complicated combination of lenses.
Ques3.
Which of the following phenomenonc contributes significantly to the reddish
appearance of the sun at sunrise or sunset?
(a) Dispersion of light
(b) Scattering of light
(c) Total internal Reflection
(d) Reflection of light from the earth
Ques4.
The focal length of the eye lens increases when eye muscles.
(a) are relaxed and lens becomes thinner
(b) contract and lens becomes thicker
(c) are relaxed and lens becomes thicker
(d) Contract and lens becomes thinner.
Ques5.
The human eye can focus objects at different distances by adjusting the focal length
of the eye lens. This is due to
(a) Presbyopia
(b) Accommodation
(c) Near-sightedness
(d) Far-sightedness
(Very Short Questions)
Ques6.
Define power of accommodation?
Ques7.
Which part of the human eye provides most of the refraction for the light rays
entering the eye?
Ques8.
What happens to the pupil of the eye when the light is very bright?
Ques9.
Name the muscle responsible for bringing change in the focal length of the eye lens?
Ques10.
What is the nature of image formed on the retina of the eye?
(2Mark Questions)
Ques11.
The far point of a myopic person is 80 cm in front of the eye. What is the nature and power of the lens required to correct the problem.
Ques12.
Name the part of the eye that
(a) determines the colour of a person’s eye
(b) Controls the amount of light entering the eye
Ques13.
State the role of eye lens in the human eye?
Ques14.
A student has difficulty reading the blackboard while sitting in the last row. What
Could be the defect the child is suffering from? How can it be corrected?
Ques15.
A person wears eye glass of focal length 70 cm what is the far point of the person?
(5 Mark Questions, Attempt any 2)
Ques16.
A 14 year old student is not able to see clearly the questions written of the black
board placed at a distance of 5 m from him.
(a) Name the defect of vision he is suffering from?
(b) Draw the diagram to show this defect?
(c) Name the type of lens used to correct this defect?
(d) Name two possible cause of this defect.
(e) Draw the diagram to show how this defect can be corrected.
Ques17.
(a) Explain the following terms used in relation to defects in vision and correction provided by them:
(i) Myopia (ii) Astigmatism (iii) Bifocal lenses (iv) Far-sightedness.
(i) Myopia (ii) Astigmatism (iii) Bifocal lenses (iv) Far-sightedness.
(b) Why is the normal eye unable to focus on an object placed within 10 cm from the eye?
Ques18.
Make a diagram to show how hypermetropia is corrected. The near point of a
hypermetropic eye is 1 m. What is the power of the lens required to correct this defect?
Assume that near point of the normal eye is 25 cm.
