Myopia and Its Correction

Q.

Statement1: Myopia is corrected by the use of the concave lens.
statement 2: In myopia, the converging power of eye lens increases.

1. Statement 1 and 2 are correct but statement 2 is not the reason for statement 1.
2. Statement 1 and 2 are correct and statement 2 is the correct reason for statement 1.
3. Both statements are wrong.
4. Statement 1 is correct but statement 2 is incorrect.

Q.

The human eye can focus on objects at different distances by adjusting the focal length of the eye lens. This is due to

1. Presbyopia

2. Accommodation

3. Near-sightedness

4. Far-sightedness

Q.

A person suffering from myopia will need concave lenses for correction.

1. True

2. False

Q.

Myopia (short-sightedness) is a defect in human eyes in which the image formed

1. in front of the retina and can be corrected by using a concave lens.

2. in front of the retina and can be corrected by using convex lens.

3. behind the retina and can be corrected by using a concave lens.

4. behind the retina and can be corrected by using a convex lens.

Q.

A person with a myopia can see near by objects clearly but cannot see distant object distinctly.

1. True

2. False

Q.

Draw ray diagrams showing a hypermetropic eye and its correction using a suitable optical device.

Q.

What is cataract?

1. A condition in which eyeballs become larger than normal
2. A condition, in old age, in which eyesight becomes foggy
3. A condition in which people do not recognise colours
4. A condition in which eyeballs become smaller than normal

Q.

Myopia can be corrected using?

1. Using convex lens of suitable power

2. Using concave lens of suitable power

3. Using convex mirror of suitable power

4. Cannot be corrected

Q.

The property related to the sense of continuity of vision is called

1. persistence of vision

2. colour blindness

3. optical illusion

4. none of these

Q.

A person who can see nearby objects clearly, but cannot see distant objects distinctly is said to be suffering from

1. myopia

2. hypermetropia

3. near sightedness

4. both a and c

Q.

Rahul had a far point of vision less than infinity. What kind of disease he is suffering from?

1. Presbyopia

2. Astigmatism

3. Hypermetropia

4. Myopia

Q.

What type of lens is used to correct each of the following defects of eye?

Long- sightedness

Q. Which one is incorrect match?

1. Olfactory - Smell
2. Algesireceptor - Pain
3. Myopia - Biconvex lens
4. Organ of Corti - Sensory and supporting cells

Q. Name the type of lens used to correct this defect.

Q. The variation in focal lengths of the human eye is caused by changing the curvature of the eye lens.

1. False
2. True

Q. What is Myopia? Give its reasons. Explain with the help of a labelled ray diagram, how it is corrected?

Q. ABCD shows the walls of a room such that AD = BC = 10 m and AB = CD = 6 m. The wall BC has a full length plane mirror. A camera is placed at the mid-point of the wall AD. Now to take clear image of the point D, the camera should be focused at

ABCD, एक कमरे की दीवारों को इस प्रकार दर्शाता है कि AD = BC = 10 m तथा AB = CD = 6 m है। दीवार BC की सम्पूर्ण लम्बाई पर एक समतल दर्पण है। एक कैमरे को दीवार AD के मध्य-बिन्दु पर रखा जाता है। अब बिन्दु D का स्पष्ट प्रतिबिम्ब लेने के लिए, कैमरे को केन्द्रित किया जाना चाहिए

1. 12 m
   
   12 m पर
2. 11 m
   
   11 m पर
3. 17 m
   
   17 m पर
4. 13 m
   
   13 m पर

Q. Myopia or near sightedness is a defect of eyes in which

1. The diameter of eyeball is longer than usual and the image is formed slightly in front of retina
2. The diameter of the eyeball is normal and the image is formed slightly behind the retina due to faulty lens
3. The curvature of the cornea is irregular so, that only some portion of the object is seen properly
4. The diameter of eyeball is normal but the image is formed at the blind spot

Q. When the light rays converge at a point in front of the retina and then divert to form a blurred image on it, the defect is known as

1. Myopia
2. Hypermetropia
3. Astigmatism
4. Presbiopia

Q.

Which one is Nearsightedness?

A. Myopia

B. Hypermetropia

C. Astigmatism

D. None of these

1. A

2. B

3. C

4. D

Q. A person needs a lens of power $+2\text{D}$ for correcting their near-sightedness. What is the focal length of the lens required to correct the defect?

1. $2\text{m}$
2. $0.5\text{cm}$
3. $20\text{cm}$
4. $50\text{cm}$

Q. In the myopia eye defect, the light rays from iris

1. Do not enter the eye at all
2. Come to a focus at back of retina
3. Come to a focus in front of the retina
4. Come to a focus in between retina and iris

Q.

Due to some accident, If eyeball elongates. Then that person is said to be affected by?

1. Myopic defect

2. Presbyopic defect

3. Hypermetropic Defect

4. None of these

Q.

Differentiate between the following pairs on the basis of what is mentioned within brackets:

(b) Near vision and Distant vision (Shape of the lens)

Q. Short sightedness is otherwise known as

1. Hyperopia
2. Presbyopia
3. Astigmatism
4. Myopia

Q. Too short eye ball and too flat lens produce

1. Near sightedness
2. Astigmatism
3. Far sightedness
4. Presbyopia

Q. Name the defect shown in the diagram.

Q. The hyperopic eye can be corrected using --- lens.

1. concave
2. convex
3. plano convex
4. plano concave

Q. Short sightedness or myopic vision is corrected by wearing

1. Concave lens
2. Convex lens
3. Biconcave lens
4. Biconvex lens

Q. A person wears convex lenses for proper vision. Without glasses the image of the object is produced

1. On blind spot
2. On yellow spot
3. In front of retina
4. Behind the retina