# ICSE Class 10th Physics 2 – Light MCQs

#### A well cut diamond appears bright because ____.

Correct! Wrong!

A well cut diamond appears bright because of total internal reflection of light in the diamond.

#### Magnification is ____ when the size of the image is equal to the size of the object.

Correct! Wrong!

The ratio of size of the image to the size of the object is called magnification. Magnification is unity when the size of the image is equal to the size of the object.

#### Using a concave lens, a diminished, virtual and erect image of the object is obtained, when the object lies ____.

Correct! Wrong!

Irrespective of the position, a concave lens always forms a diminished, virtual and erect image of the object. Hence, using a concave lens, a diminished, virtual and erect image of the object is obtained, when the object lies anywhere between the optic centre and infinity.

#### Which of the following is the correct statement?

Correct! Wrong!

The angle between the incident ray and the normal is known as the angle of incidence. The angle of incidence is not always equal to the angle of refraction.

#### Half the aperture of a converging lens covered with a stop is used to form an image on a screen. Which of the following is true?

Correct! Wrong!

When half the aperture of a converging lens covered with a stop is used, complete image of the object is formed with less intensity.

#### The power of a lens is + 2.0 D. Then the focal length of the lens is ____.

Correct! Wrong!

Given, P = + 2.0 D; f =? As, f=1p f=1002 f = 50 cm Hence, the focal length of the lens is 50 cm.

#### A coin present at the bottom of a beaker filled with water appears to be raised. This is due to ____ of light.

Correct! Wrong!

Due to refraction, the coin present at the bottom of a beaker filled with water appears to be raised.

#### ____ is a point on the axis of a lens such that any light ray passing through this point emerges without refraction.

Correct! Wrong!

Optic centre is a point on the axis of a lens such that any light ray passing through this point emerges without refraction.

#### It is possible to observe total internal reflection when a ray travels from ____.

Correct! Wrong!

Total internal reflection takes place when the following conditions are satisfied. 1. When the ray travels from the denser to the rarer medium. 2. The angle of incidence is greater than critical angle. The increasing order of optical density of given mediums is air, water and glass. Hence, total internal reflection is possible when a ray travels from glass to water.

#### When a ray is travelling from a rarer medium to the denser medium, the ray will move away from the normal.

Correct! Wrong!

When a ray is travelling from a rarer medium to the denser medium, the ray will move towards the normal.

#### An isosceles glass prism having one angle 90° is called ____prism.

Correct! Wrong!

An isosceles glass prism having one angle 90° is called totally reflecting prism because, it turns the ray by 90° due to total internal reflection.

#### Which of the following medium is optically more denser?

Correct! Wrong!

Diamond is optically more denser compared to others.

#### The refractive index of a material does not depend upon the____.

Correct! Wrong!

Refractive index of a material depends upon the nature of the material of the medium, density of the medium, and wavelength of the light. Hence, the refractive index of a material does not depend upon the frequency of the light.

#### Which of the following is not an example of refraction?

Correct! Wrong!

Image in a mirror is an example of the reflection phenomenon.

#### Diopters is the unit of optical ____.

Correct! Wrong!

Diopters is the unit of optical power.

#### A biconvex lens of refractive index 'μ', behaves as a divergent lens in water and behaves as a convergent lens in air. The refractive index of water is 1.33 and that of air is 1. Which of the following is true?

Correct! Wrong!

When a lens is place in a medium, 1. Its nature remains same, if the refractive index of the medium is less than that of the lens. 2. Its nature changes, if the refractive index of the medium is more than that of the lens. Hence, 1 < μ < 1.33.

#### The main cause for twinkling of stars is ____ of light.

Correct! Wrong!

The refractive index of atmosphere changes continuously and randomly due to which the amount of light reaching us is varying continuously. Hence, the stars appear to be twinkling due to atmospheric refraction.

#### The lens which is thicker at the center and thinner at the periphery is called a ____ lens.

Correct! Wrong!

A convex lens is thicker at the center and thinner at the periphery.

#### ____ can be thought of as a series of tiny refracting prisms, each of which refracts light to produce their own image.

Correct! Wrong!

Lenses can be thought of as a series of tiny refracting prisms, each of which refracts light to produce their own image. When these prisms act together, they produce a bright image focused at a point.

#### Light travels faster in____.

Correct! Wrong!

Light travels faster in vacuum. It has a velocity, equal to 3 × 108m/s.

#### A ____ lens is used in a camera.

Correct! Wrong!

A convex lens is used in a camera.

#### A ____ is a diverging lens.

Correct! Wrong!

A concave lens is the diverging lens.

#### When a ray is travelling from a rarer medium to the denser medium, the ray will move away from the normal.

Correct! Wrong!

When a ray is travelling from a rarer medium to the denser medium, the ray will move towards the normal.

#### Arrange the following substances in increasing order of velocity of light in the medium, whose refractive indices are given below: glycerin = 1.48, dense flint = 1.62, water = 1.33, diamond = 2.1.

Correct! Wrong!

Velocity of light in a medium is inversely proportional to refractive index of the medium. Hence, increasing order of velocity of light in the given mediums is diamond, dense flint, glycerin and water.

#### In order to get an erect and virtual image of an object using a convex lens, the position of the object should ____.

Correct! Wrong!

When an object is placed between the focus and optic centre of a convex lens, it form erect and virtual image. Hence, in order to get an erect and virtual image of an object using a convex lens, the position of the object should lie between the focus and optic centre.

ICSE Class 10th Physics 2 - Light MCQs
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