# NCERT solutions for Class 10 Science chapter 10 - Light – Reflection and Refraction [Latest edition]

## Chapter 10: Light – Reflection and Refraction

[Page 168]

### NCERT solutions for Class 10 Science Chapter 10 Light – Reflection and Refraction [Page 168]

Q 1 | Page 168

Define the principal focus of a concave mirror.

Q 2 | Page 168

The radius of curvature of a spherical mirror is 20 cm. What is its focal length?

Q 3 | Page 168

Name the mirror that can give an erect and enlarged image of an object.

Q 4 | Page 168

Why do we prefer a convex mirror as a rear-view mirror in vehicles?

[Page 171]

### NCERT solutions for Class 10 Science Chapter 10 Light – Reflection and Refraction [Page 171]

Q 1 | Page 171

Find the focal length of a convex mirror whose radius of curvature is 32 cm.

Q 2 | Page 171

A concave mirror produces three times magnified (enlarged) real image of object placed at 10 cm in front of it. Where is the image located?

[Page 176]

### NCERT solutions for Class 10 Science Chapter 10 Light – Reflection and Refraction [Page 176]

Q 1 | Page 176

A ray of light travelling in air enters obliquely into water. Does the light ray bend towards the normal or away from the normal? Why?

Q 2 | Page 176

Light enters from air to glass having refractive index 1.50. What is the speed of light in the glass? The speed of light in vacuum is 3 × 108 m s−1.

Q 3 | Page 176

Find out, from Table, the medium having highest optical density. Also find the medium with lowest optical density.

 Material   medium Refractive index Material medium Refractive   index Air 1.0003 Canada Balsam 1.53 Ice 1.31 – – Water 1.33 Rock salt 1.54 Alcohol 1.36 – – Kerosene 1.44 Carbon disulphide 1.63 Fused   quartz 1.46 Dense   flint glass 1.65 Turpentine oil 1.47 Ruby 1.71 Benzene 1.50 Sapphire 1.77 Crown   glass 1.52 Diamond 2.42
Q 4 | Page 176

You are given kerosene, turpentine and water. In which of these does the light travel fastest? Use the information given in Table.

 Materialmedium Refractive index Material medium Refractive   index Air 1.0003 Canada Balsam 1.53 Ice 1.31 – – Water 1.33 Rock salt 1.54 Alcohol 1.36 – – Kerosene 1.44 Carbon disulphide 1.63 Fusedquartz 1.46 Denseflint glass 1.65 Turpentine oil 1.47 Ruby 1.71 Benzene 1.50 Sapphire 1.77 Crownglass 1.52 Diamond 2.42
Q 5 | Page 176

The refractive index of diamond is 2.42. What is the meaning of this statement?

[Page 184]

### NCERT solutions for Class 10 Science Chapter 10 Light – Reflection and Refraction [Page 184]

Q 1 | Page 184

Define 1 dioptre of power of a lens.

Q 2 | Page 184

A convex lens forms a real and inverted image of a needle at a distance of 50 cm from it. Where is the needle placed in front of the convex lens if the image is equal to the size of the object? Also, find the power of the lens.

Q 3 | Page 184

Find the power of a concave lens of focal length 2 m.

[Pages 185 - 186]

### NCERT solutions for Class 10 Science Chapter 10 Light – Reflection and Refraction [Pages 185 - 186]

Q 1 | Page 185

Which one of the following materials cannot be used to make a lens?

• Water

• Glass

• Plastic

• Clay

Q 2 | Page 185

The image formed by a concave mirror is observed to be virtual, erect and larger than the object. Where should be the position of the object?

• Between the principal focus and the centre of curvature

• At the centre of curvature

• Beyond the centre of curvature

• Between the pole of the mirror and its principal focus.

Q 3 | Page 185

Where should an object be placed in front of a convex lens to get a real image of the size of the object?

• At the principal focus of the lens

• At twice the focal length

• At infinity

• Between the optical centre of the lens and its principal focus

Q 4 | Page 185

A spherical mirror and a thin spherical lens have each a focal length of -15 cm. The mirror and the lens are likely to be

• both concave

• both convex

• the mirror is concave and the lens is convex

• the mirror is convex, but the lens is concave

Q 5 | Page 186

No matter how far you stand from a mirror, your image appears erect. The mirror is likely to be

• plane

• concave

• convex

• either plane or convex

Q 6 | Page 186

Which of the following lenses would you prefer to use while reading small letters found in a dictionary?

• A convex lens of focal length 50 cm

• A concave lens of focal length 50 cm

• A convex lens of focal length 5 cm

• A concave lens of focal length 5 cm

Q 7 | Page 186

We wish to obtain an erect image of an object, using a concave mirror of focal length 15 cm. What should be the range of distance of the object from the mirror? What is the nature of the image? Is the image larger or smaller than the object? Draw a ray diagram to show the image formation in this case.

Q 8.1 | Page 186

Name the type of mirror used in the following situation.

Q 8.2 | Page 186

Name the type of mirror used in the following situation.

Side/rear-view mirror of a vehicle

Q 8.3 | Page 186

Name the type of mirror used in the following situation.

Solar furnace

Q 9 | Page 186

One-half of a convex lens is covered with a black paper. Will this lens produce a complete image of the object? Verify your answer experimentally. Explain your observations.

Q 10 | Page 186

An object 5 cm in length is held 25 cm away from a converging lens of focal length 10 cm. Draw the ray diagram and find the position, size and the nature of the image formed.

Q 11 | Page 186

A concave lens of focal length 15 cm forms an image 10 cm from the lens. How far is the object placed from the lens? Draw the ray diagram.

Q 12 | Page 186

An object is placed at a distance of 10 cm from aconvex mirror of focal length 15 cm. Find the position and nature of the image.

Q 13 | Page 186

What is the magnification of the images formed by plane mirrors and why?

Q 14 | Page 186

An object 5 cm is placed at a distance of 20 cm in front of a convex mirror of radius of curvature 30 cm. Find the position, nature and size of the image.

Q 15 | Page 186

An object of size 7.0 cm is placed at 27 cm in front of a concave mirror of focal length 18 cm. At what distance from the mirror should a screen be placed, so that a sharp focused image can be obtained? Find the size and the nature of the image.

Q 16 | Page 186

Find the focal length of a lens of power -2.0 D. What type of lens is this?

Q 17 | Page 186

A doctor has prescribed a corrective lens of power +1.5 D. Find the focal length of the lens. Is the prescribed lens diverging or converging?

## NCERT solutions for Class 10 Science chapter 10 - Light – Reflection and Refraction

NCERT solutions for Class 10 Science chapter 10 (Light – Reflection and Refraction) include all questions with solution and detail explanation. This will clear students doubts about any question and improve application skills while preparing for board exams. The detailed, step-by-step solutions will help you understand the concepts better and clear your confusions, if any. Shaalaa.com has the CBSE Class 10 Science solutions in a manner that help students grasp basic concepts better and faster.

Further, we at Shaalaa.com provide such solutions so that students can prepare for written exams. NCERT textbook solutions can be a core help for self-study and acts as a perfect self-help guidance for students.

Concepts covered in Class 10 Science chapter 10 Light – Reflection and Refraction are Spherical Mirrors, Concave Mirror, Convex Mirror, Concave Lens, Refraction of Light, Image Formation by Convex Mirror, Sign Convention for Reflection by Spherical Mirrors, Mirror Equation/Formula, Images Formed by Spherical Mirrors, Image Formation by Concave Mirror, Reflection of Light, Law of Reflection of Light, Linear Magnification (M) Due to Spherical Mirrors, Magnification Due to Spherical Lenses, Power of a Lens, Mirrors and Its Types, Plane Mirror and Reflection, Rules for the Construction of Image Formed by a Spherical Mirror, Refraction of Light Through a Rectangular Glass Slab, Law of Refraction of Light, Refractive Index, Spherical Lens, Images Formed by Sperical Lenses, Guideline for Image Formation Due to Refraction Through a Convex and Concave Lens, Images Formed Due to Refraction Through a Concave Lens, Convex Lens, Images Formed Due to Refraction Through a Convex Lens, Sign Convention for Spherical Lenses, Lens Formula, Spherical Mirrors, Concave Mirror, Convex Mirror, Concave Lens, Refraction of Light, Image Formation by Convex Mirror, Sign Convention for Reflection by Spherical Mirrors, Mirror Equation/Formula, Images Formed by Spherical Mirrors, Image Formation by Concave Mirror, Reflection of Light, Law of Reflection of Light, Linear Magnification (M) Due to Spherical Mirrors, Magnification Due to Spherical Lenses, Power of a Lens, Mirrors and Its Types, Plane Mirror and Reflection, Rules for the Construction of Image Formed by a Spherical Mirror, Refraction of Light Through a Rectangular Glass Slab, Law of Refraction of Light, Refractive Index, Spherical Lens, Images Formed by Sperical Lenses, Guideline for Image Formation Due to Refraction Through a Convex and Concave Lens, Images Formed Due to Refraction Through a Concave Lens, Convex Lens, Images Formed Due to Refraction Through a Convex Lens, Sign Convention for Spherical Lenses, Lens Formula.

Using NCERT Class 10 solutions Light – Reflection and Refraction exercise by students are an easy way to prepare for the exams, as they involve solutions arranged chapter-wise also page wise. The questions involved in NCERT Solutions are important questions that can be asked in the final exam. Maximum students of CBSE Class 10 prefer NCERT Textbook Solutions to score more in exam.

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