UPSC Exam  >  UPSC Tests  >  Science & Technology for UPSC CSE  >  Test: Defects of Vision - UPSC MCQ

Test: Defects of Vision - UPSC MCQ


Test Description

15 Questions MCQ Test Science & Technology for UPSC CSE - Test: Defects of Vision

Test: Defects of Vision for UPSC 2024 is part of Science & Technology for UPSC CSE preparation. The Test: Defects of Vision questions and answers have been prepared according to the UPSC exam syllabus.The Test: Defects of Vision MCQs are made for UPSC 2024 Exam. Find important definitions, questions, notes, meanings, examples, exercises, MCQs and online tests for Test: Defects of Vision below.
Solutions of Test: Defects of Vision questions in English are available as part of our Science & Technology for UPSC CSE for UPSC & Test: Defects of Vision solutions in Hindi for Science & Technology for UPSC CSE course. Download more important topics, notes, lectures and mock test series for UPSC Exam by signing up for free. Attempt Test: Defects of Vision | 15 questions in 20 minutes | Mock test for UPSC preparation | Free important questions MCQ to study Science & Technology for UPSC CSE for UPSC Exam | Download free PDF with solutions
Test: Defects of Vision - Question 1

What is the main cause of myopia?

Detailed Solution for Test: Defects of Vision - Question 1

Myopia, or shortsightedness, is primarily caused by the elongation of the eyeball, leading to the inability to see distant objects clearly. This elongation affects the focusing of light onto the retina, resulting in blurry vision for faraway objects.

Test: Defects of Vision - Question 2

A boy is wearing glasses and says that he cannot see the object kept at a distance without glasses. He is suffering from

Detailed Solution for Test: Defects of Vision - Question 2

As Myopia is a defect of vision in which a person cannot see the distant object clearly. This can be corrected by using the concave lens of appropriate focal length

1 Crore+ students have signed up on EduRev. Have you? Download the App
Test: Defects of Vision - Question 3

Choose the correctly matched pair:

Detailed Solution for Test: Defects of Vision - Question 3

Explanation:

  • Option A: (a) Myopia - Decrease in focal length of the eye lens. This is correctly matched.
    Myopia, or shortsightedness, is caused by a decrease in the focal length of the eye lens, making it more convergent. This causes distant objects to appear blurry.
  • Option B: (b) Hypermetropia - Elongation of the eyeball. This is incorrect.
    Hypermetropia, or farsightedness, is typically caused by a shorter than normal eyeball or a less convergent eye lens, not by elongation of the eyeball.
  • Option C: (c) Astigmatism - Genetic disorder. This is incorrect.
    Astigmatism is not necessarily a genetic disorder. It is usually caused by an irregular shape of the cornea or lens, leading to blurred vision.
  • Option D: (d) Colour blindness - Concave lens for correction. This is incorrect.
    Colour blindness is a genetic disorder that affects the ability to distinguish between certain colors. It cannot be corrected by lenses like a concave lens, which is used to correct myopia. Therefore, the correctly matched pair is Option A: Myopia - Decrease in focal length of the eye lens.
Test: Defects of Vision - Question 4

Cataract can be cured by

Detailed Solution for Test: Defects of Vision - Question 4

Surgery to treat cataracts involves removing the clouded lens and replacing it with a synthetic new one. This procedure is safe and very effective.They're researching eye drops that may dissolve cataracts so patients don't have to go to surgery.

Test: Defects of Vision - Question 5

Longsightedness (or hypermetropia) is the defect due to which the eye is not able to see clearly the nearby objects though it can see the distant objects clearly because its near point is farther away from the normal near point, which is about ____ for an adult.

Detailed Solution for Test: Defects of Vision - Question 5

Longsightedness (or hypermetropia) causes the near point of the eye to be farther away from the normal near point, which is approximately 25 cm for an adult. This condition results in difficulty in focusing on nearby objects while maintaining clear vision of distant objects.

Test: Defects of Vision - Question 6

We use __________ lens to correct Hypermetropia

Detailed Solution for Test: Defects of Vision - Question 6

Hypermetropia can be corrected by using a convex lens. A convex lens converges the incoming light such that the image is formed on the retina.

Test: Defects of Vision - Question 7

If the image was formed in front of the retina rather than behind the retina, then the person would need to correct the vision problem by using a:

Detailed Solution for Test: Defects of Vision - Question 7

Nearsighted individuals have image formed in front of the retina. They must correct the problem by wearing a lens which provides for some diverging of light prior to reaching the lens of the eye. This will move the image further from the lens of the eye and back towards the retina.

Test: Defects of Vision - Question 8

Which of the following lenses is used to correct myopia (nearsightedness)?

Detailed Solution for Test: Defects of Vision - Question 8

- Myopia (Nearsightedness): A condition where distant objects appear blurry because the image forms in front of the retina.
- Corrective Lens: A concave lens is used to correct myopia.
- Concave Lens Function: It diverges light rays before they enter the eye, moving the focal point back onto the retina, allowing for clear distant vision.

Test: Defects of Vision - Question 9

The near point of a human eye is at a distance of

Detailed Solution for Test: Defects of Vision - Question 9

The near point of the eye is the minimum distance of the object from the eye, which can be seen distinctly without strain. For a normal human eye, this distance is 25 cm. The far point of the eye is the maximum distance to which the eye can see the objects clearly. The far point of the normal human eye is infinity.

Test: Defects of Vision - Question 10

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?​

Detailed Solution for Test: Defects of Vision - Question 10

For person affected with myopic condition, the image instead of forming on retina, it forms in front of it. In order to cure such type of defect, concave lens of power - 1.25D is used.

Test: Defects of Vision - Question 11

A person has near point of his vision shifted to 50 cm. What lens must be used to see an object placed at 25 cm from the eye? What is the power of the lens?

Detailed Solution for Test: Defects of Vision - Question 11

When object is placed at 25 cm, then a virtual image should form at 50 cm. 
So, u = -25 cm, v= -50 cm. 
So, 1/f = 1/-50 - 1/-25 
f = 50 cm = 0.5 m 
Power, P = 1/f = 1/0.5 =  +2D 
Therefore , a convex lens is needed.

Test: Defects of Vision - Question 12

A person with defective eyesight is unable to see objects clearly nearer than 1.5 m. He wants to read a book placed at a distance of 30 cm from his eyes. The type of a required lens and its focal length is​

Detailed Solution for Test: Defects of Vision - Question 12

This person suffers from the defect of hypermetropia.
For him u = -30cm, v = -1.5 m = -150cm
Therefore, focal length of corrective lens to be used by him is
1/f = 1/v- 1/u = 1/-150 - 1/-30 = 4/150 = 37.5cm
The positive sign shows that the lens needed is a convex lens of focal length 37.5 cm.
Hence, power of lens needed
P =1/f = 100/37.5 = 2.67D

Test: Defects of Vision - Question 13

Image is formed for the shortsighted person:

Detailed Solution for Test: Defects of Vision - Question 13

Short-sightedness (myopia) usually occurs when the eyes grow slightly too long, which means they're unable to produce a clear image of objects in the distance.

Test: Defects of Vision - Question 14
If a person with hypermetropia struggles to see objects placed closer than 50 cm, what is the power of the lens needed to correct this vision?
Detailed Solution for Test: Defects of Vision - Question 14
For hypermetropia where the near point is significantly further than normal, a convex lens with a positive power, such as +2 D, is required to converge light rays correctly on the retina.
Test: Defects of Vision - Question 15
How can presbyopia affect an individual’s vision and what type of lens is typically used to correct it?
Detailed Solution for Test: Defects of Vision - Question 15
Presbyopia impacts the ability to focus on near objects due to the loss of accommodation with age. Bifocal lenses are commonly used to address both near and far vision needs, featuring both convex and concave sections.
146 videos|358 docs|249 tests
Information about Test: Defects of Vision Page
In this test you can find the Exam questions for Test: Defects of Vision solved & explained in the simplest way possible. Besides giving Questions and answers for Test: Defects of Vision, EduRev gives you an ample number of Online tests for practice

Top Courses for UPSC

146 videos|358 docs|249 tests
Download as PDF

Top Courses for UPSC