Myopia

Q.

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?

1. converging lens of power +1.25 D

2. diverging lens of power +1.25 D

3. converging lens of power -1.25 D

4. diverging lens of power -1.25 D

Q.

A student uses a lens of focal length 40 cm and another of -20 cm. Write the nature and power of each lens.

Q. A person having myopic eye uses a concave lens of focal length 50cm.
what is the power of the lens?

Q.

An object of height 2 cm is placed at a distance of 15 CM in front of concave lens of power -100 . Find the size of the image

Q. The near point and far point of a person are at 60cm and 300 cm respectively. Find the power of lens he should use while reading 30 cm. With this lens on the eye, what maximum distance is clearly visible?

Q. A person needs a lens of power $-2.5D$ for correcting his vision. What is the defect of vision that the person is suffering from? Also, find the focal length of the lens.

1. Hypermetropia, $0.4m$
2. Hypermetropia, $-0.4m$
3. Myopia, $0.4m$
4. Myopia, $-0.4m$

Q.

Are glasses convex or concave?

Q. What is the unit of magnification?

Q. A person uses a spectacles of power –2 D. He is suffering from

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

Q.

What is one of the reasons for myopia?

Q.

The near point of a hypermetropic eye is 50cm. What is the nature and Power of the lens required to enable him to read a book at 25cm from the eye?

Q.

A person needs a lens of power $–4.5D$ for correction of her vision. (a) What kind of defect in vision is she suffering from? (b) What is the focal length of the corrective lens? (c) What is the nature of the corrective lens?

Q. Question 1
Define 1 dioptre of power of a lens.

Q.

In myopia, the image is formed:

1. Behind the retina

2. Image is not formed at

3. Retina

4. Before retina

Q.

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?

1. A diverging lens of focal length 50 cm and power + 2 D

2. A converging lens of focal lens 50 cm and power - 2 D

3. A diverging lens of focal length 50 cm and power - 2 D

4. A converging lens of focal length 50 cm and power + 2 D

Q. When two lenses 10 cm and -5cm are placed in contact then find the net power.

Q. In a myopic eye, the image of the object is formed

1. on the retina
2. in front of the retina
3. behind the retina
4. on the blind spot

Q. What is the nature of lens required to correct a myopic eye?

1. Convex
2. Concave
3. Cylindrical
4. Bifocal

Q.

The power of the lens is -2D. Is the lens concave or convex?

Q. A defective eye cannot see close objects clearly. This is because their images are formed

1. Behind retina
2. On the eye lens
3. Beyond retina
4. On the retina

Q.

The lens of a myopic person is __________ in the middle.

1. thin

2. thick

3. normal

4. cylindrical

Q.

A person having myopic eyes uses a concave lens of focal length 50 cm. What is the power of the lens?

1. - 0.02 D

2. - 2 D

3. + 2 D

4. + 0.02 D

Q.

What are the lens formula, magnification, and power of the lens?

Q.

A doctor has prescribed a corrective lens of power+1.5 doctor. Find the focal length

(a) is the prescribed lens diverging or converging

Q.

What is astigmatism and what are its effects

Q. A person needs a lens of power +2 for correcting his near vision. What is the focal length of the lens required?

Q.

Statement 1: Myopia is corrected by the use of concave lens.

Statement 2: A concave lens diverges the light coming from the object kept at infinity and makes it appear to be within the far point of myopic eye, which then acts as the object for the myopic eye thus helping to view it.

1. Statement 1 and 2 are correct and statement 2 is the correct reason for statement 1.

2. Statement 2 is correct but statement 1 is incorrect.

3. Statement 1 and 2 are correct but statement 2 is not the reason of statement 1.

4. Statement 1 is correct but statement 2 is incorrect.

Q. A person needs a lens of power $-2.5D$ for correcting his vision. What is the defect of vision that the person is suffering from? Also, find the focal length of the lens.

1. Hypermetropia, $0.4m$
2. Myopia, $0.4m$
3. Myopia, $-0.4m$
4. Hypermetropia, $-0.4m$

Q. The far point of a myopic person is $100\text{cm}$ in front of the eye. What is the nature and power of the lens required to correct the problem?

1. Convex lens, Power = $+1.5\text{D}$
2. Concave lens, Power = $-1.5\text{D}$
3. Convex lens, Power = $+1\text{D}$
4. Concave lens, Power = $-1\text{D}$

Q.

Myopia can be corrected by using which lens?