Question 1

What happens when an opaque object blocks the path of light? (Page 157)

Accepted Answer

When light falls on an opaque object, it cannot pass through, and a dark region called a shadow appears on the screen or surface behind the object.

Source: This question is from Light Shadows and Reflections, Science &mdash; Class 7, CBSE Board.
Key Concepts CoveredThis question tests your understanding of the following concepts from the chapter Light Shadows and Reflections: Happens, Opaque, Object, Blocks, Path, Light. These are fundamental topics in Science that students are expected to master as part of the CBSE Class 7 curriculum.A thorough understanding of these concepts will help you answer similar questions confidently in your CBSE examinations. These topics are frequently tested in both objective and subjective sections of Science papers. We recommend revising the relevant section of your textbook alongside practising these solved examples to build a strong foundation.
How to Approach This QuestionRead the question carefully and identify what is being asked. Break down complex questions into smaller parts. Use the terminology and concepts discussed in this chapter. Structure your answer logically — begin with a definition or key statement, then provide supporting details. Review your answer to ensure it addresses all parts of the question completely.
Key Points to RememberRead the question carefully and identify all parts before answering.
Use the terminology specific to this subject and chapter.
Review the textbook content for this chapter before attempting questions.
Practice writing concise, well-structured answers within time limits.
Related Questions from Light Shadows and ReflectionsQ10: The shadow of a ball is formed on a wall by placing the ball in front of a fixed torch as shown in...
Q11: Based on Fig. 11.18, match the position of the torch in Column A with the characteristics of the...
Q12: Suppose you view the tree shown in Fig. 11.19 through a pinhole camera. Sketch the outline of the...
Q13: Write your name on a piece of paper and hold it in front of a plane mirror such that the paper is...
Q14: Measure the length of your shadow at 9 AM, 12 PM, and 4 PM with the help of your friend. Write down...
Practice more questions from Light Shadows and Reflections &mdash; Science, Class 7 CBSE

Chapter 11: Light
    Reflection follows two laws: angle of incidence equals angle of reflection, and all rays are in the same plane. Plane mirror images are virtual, erect, same size, and laterally inverted. Concave mirrors converge light (used in torches, dentist mirrors). Convex mirrors diverge light (used in rear-view mirrors). Dispersion splits white light into VIBGYOR through a prism. Rainbows are natural dispersion by water droplets.
    Theme: Physics | Difficulty: Age-appropriate for Class VII

Key Formulas & Equations

Formula / Equation
        When to Use

Law 1: Angle of incidence = Angle of reflection (&angle;i = &angle;r)First law of reflection
      VIBGYOR: Violet, Indigo, Blue, Green, Yellow, Orange, RedSpectrum colours in order

Must-Know Concepts
  
    Two laws of reflection: &angle;i = &angle;r; same plane
    Plane mirror: virtual, erect, same size, laterally inverted, equal distance behind
    Lateral inversion: left-right swap (AMBULANCE written in reverse)
    Concave mirror: converges light, uses = torch, headlight, dentist, solar cooker
    Convex mirror: diverges light, wider view, uses = rear-view mirror
    Real image: on screen; Virtual image: cannot be on screen
    Dispersion: white light through prism gives VIBGYOR spectrum

Common Mistakes to Avoid
    
      Thinking plane mirror image is real &mdash; it is virtual
      Confusing lateral inversion with upside-down
      Thinking white light is pure &mdash; it is a mixture of 7 colours

Scoring Tips
    
      Draw ray diagrams with incident ray, normal, reflected ray, and angles
      List 5 properties of plane mirror image
      Compare concave and convex mirrors with uses

Question 2

Match the items in Column A with those in Column B.

Accepted Answer

Column A
Column B

(i) Pinhole
(c) Forms an inverted image

(ii) Opaque object
(a) Blocks light completely camera

(iii) Transparent object
(d) Light passes almost completely through it

(iv) Shadow
(b) The dark region formed behind the object

Chapter 11: Light
    Reflection follows two laws: angle of incidence equals angle of reflection, and all rays are in the same plane. Plane mirror images are virtual, erect, same size, and laterally inverted. Concave mirrors converge light (used in torches, dentist mirrors). Convex mirrors diverge light (used in rear-view mirrors). Dispersion splits white light into VIBGYOR through a prism. Rainbows are natural dispersion by water droplets.
    Theme: Physics | Difficulty: Age-appropriate for Class VII

Key Formulas & Equations

Formula / Equation
        When to Use

Law 1: Angle of incidence = Angle of reflection (&angle;i = &angle;r)First law of reflection
      VIBGYOR: Violet, Indigo, Blue, Green, Yellow, Orange, RedSpectrum colours in order

Must-Know Concepts
  
    Two laws of reflection: &angle;i = &angle;r; same plane
    Plane mirror: virtual, erect, same size, laterally inverted, equal distance behind
    Lateral inversion: left-right swap (AMBULANCE written in reverse)
    Concave mirror: converges light, uses = torch, headlight, dentist, solar cooker
    Convex mirror: diverges light, wider view, uses = rear-view mirror
    Real image: on screen; Virtual image: cannot be on screen
    Dispersion: white light through prism gives VIBGYOR spectrum

Common Mistakes to Avoid
    
      Thinking plane mirror image is real &mdash; it is virtual
      Confusing lateral inversion with upside-down
      Thinking white light is pure &mdash; it is a mixture of 7 colours

Scoring Tips
    
      Draw ray diagrams with incident ray, normal, reflected ray, and angles
      List 5 properties of plane mirror image
      Compare concave and convex mirrors with uses

Question 3

In a mirror, I can also see my face. Is that also due to the reflection of light? (Page 160)

Accepted Answer

Yes, we can see our face in a mirror due to the reflection of light.

Source: This question is from Light Shadows and Reflections, Science &mdash; Class 7, CBSE Board.
Key Concepts CoveredThis question tests your understanding of the following concepts from the chapter Light Shadows and Reflections: Mirror, See, Face, Due, Reflection, Light. These are fundamental topics in Science that students are expected to master as part of the CBSE Class 7 curriculum.A thorough understanding of these concepts will help you answer similar questions confidently in your CBSE examinations. These topics are frequently tested in both objective and subjective sections of Science papers. We recommend revising the relevant section of your textbook alongside practising these solved examples to build a strong foundation.
How to Approach This QuestionRead the question carefully and identify what is being asked. Break down complex questions into smaller parts. Use the terminology and concepts discussed in this chapter. Structure your answer logically — begin with a definition or key statement, then provide supporting details. Review your answer to ensure it addresses all parts of the question completely.
Key Points to RememberRead the question carefully and identify all parts before answering.
Use the terminology specific to this subject and chapter.
Review the textbook content for this chapter before attempting questions.
Practice writing concise, well-structured answers within time limits.
Related Questions from Light Shadows and ReflectionsQ10: The shadow of a ball is formed on a wall by placing the ball in front of a fixed torch as shown in...
Q11: Based on Fig. 11.18, match the position of the torch in Column A with the characteristics of the...
Q12: Suppose you view the tree shown in Fig. 11.19 through a pinhole camera. Sketch the outline of the...
Q13: Write your name on a piece of paper and hold it in front of a plane mirror such that the paper is...
Q14: Measure the length of your shadow at 9 AM, 12 PM, and 4 PM with the help of your friend. Write down...
Practice more questions from Light Shadows and Reflections &mdash; Science, Class 7 CBSE

Chapter 11: Light
    Reflection follows two laws: angle of incidence equals angle of reflection, and all rays are in the same plane. Plane mirror images are virtual, erect, same size, and laterally inverted. Concave mirrors converge light (used in torches, dentist mirrors). Convex mirrors diverge light (used in rear-view mirrors). Dispersion splits white light into VIBGYOR through a prism. Rainbows are natural dispersion by water droplets.
    Theme: Physics | Difficulty: Age-appropriate for Class VII

Key Formulas & Equations

Formula / Equation
        When to Use

Law 1: Angle of incidence = Angle of reflection (&angle;i = &angle;r)First law of reflection
      VIBGYOR: Violet, Indigo, Blue, Green, Yellow, Orange, RedSpectrum colours in order

Must-Know Concepts
  
    Two laws of reflection: &angle;i = &angle;r; same plane
    Plane mirror: virtual, erect, same size, laterally inverted, equal distance behind
    Lateral inversion: left-right swap (AMBULANCE written in reverse)
    Concave mirror: converges light, uses = torch, headlight, dentist, solar cooker
    Convex mirror: diverges light, wider view, uses = rear-view mirror
    Real image: on screen; Virtual image: cannot be on screen
    Dispersion: white light through prism gives VIBGYOR spectrum

Common Mistakes to Avoid
    
      Thinking plane mirror image is real &mdash; it is virtual
      Confusing lateral inversion with upside-down
      Thinking white light is pure &mdash; it is a mixture of 7 colours

Scoring Tips
    
      Draw ray diagrams with incident ray, normal, reflected ray, and angles
      List 5 properties of plane mirror image
      Compare concave and convex mirrors with uses

Question 4

Oh! Now I realise why
is written on an ambulance. It reads ‘AMBULANCE’ when viewed from the rear-view mirrors of the vehicle ahead of the ambulance. (Page 162)

Accepted Answer

The word ‘AMBULANCE’ is written in an inverted (mirror) form on the front of an ambulance so that it appears correctly when seen in the rear-view mirror of a vehicle. This happens due to lateral inversion caused by the mirror.

Chapter 11: Light
    Reflection follows two laws: angle of incidence equals angle of reflection, and all rays are in the same plane. Plane mirror images are virtual, erect, same size, and laterally inverted. Concave mirrors converge light (used in torches, dentist mirrors). Convex mirrors diverge light (used in rear-view mirrors). Dispersion splits white light into VIBGYOR through a prism. Rainbows are natural dispersion by water droplets.
    Theme: Physics | Difficulty: Age-appropriate for Class VII

Key Formulas & Equations

Formula / Equation
        When to Use

Law 1: Angle of incidence = Angle of reflection (&angle;i = &angle;r)First law of reflection
      VIBGYOR: Violet, Indigo, Blue, Green, Yellow, Orange, RedSpectrum colours in order

Must-Know Concepts
  
    Two laws of reflection: &angle;i = &angle;r; same plane
    Plane mirror: virtual, erect, same size, laterally inverted, equal distance behind
    Lateral inversion: left-right swap (AMBULANCE written in reverse)
    Concave mirror: converges light, uses = torch, headlight, dentist, solar cooker
    Convex mirror: diverges light, wider view, uses = rear-view mirror
    Real image: on screen; Virtual image: cannot be on screen
    Dispersion: white light through prism gives VIBGYOR spectrum

Common Mistakes to Avoid
    
      Thinking plane mirror image is real &mdash; it is virtual
      Confusing lateral inversion with upside-down
      Thinking white light is pure &mdash; it is a mixture of 7 colours

Scoring Tips
    
      Draw ray diagrams with incident ray, normal, reflected ray, and angles
      List 5 properties of plane mirror image
      Compare concave and convex mirrors with uses

Question 5

Can we see an image of an object only in a mirror or are there some other ways as well? (Page 162)

Accepted Answer

We can see an image of an object on a screen, through transparent materials, or in devices like a pinhole camera.NCERT Class 7 Science Chapter 11 Question Answer Light Shadows and Reflections (Exercise)Let Us Enhance Our Learning

Chapter 11: Light
    Reflection follows two laws: angle of incidence equals angle of reflection, and all rays are in the same plane. Plane mirror images are virtual, erect, same size, and laterally inverted. Concave mirrors converge light (used in torches, dentist mirrors). Convex mirrors diverge light (used in rear-view mirrors). Dispersion splits white light into VIBGYOR through a prism. Rainbows are natural dispersion by water droplets.
    Theme: Physics | Difficulty: Age-appropriate for Class VII

Key Formulas & Equations

Formula / Equation
        When to Use

Law 1: Angle of incidence = Angle of reflection (&angle;i = &angle;r)First law of reflection
      VIBGYOR: Violet, Indigo, Blue, Green, Yellow, Orange, RedSpectrum colours in order

Must-Know Concepts
  
    Two laws of reflection: &angle;i = &angle;r; same plane
    Plane mirror: virtual, erect, same size, laterally inverted, equal distance behind
    Lateral inversion: left-right swap (AMBULANCE written in reverse)
    Concave mirror: converges light, uses = torch, headlight, dentist, solar cooker
    Convex mirror: diverges light, wider view, uses = rear-view mirror
    Real image: on screen; Virtual image: cannot be on screen
    Dispersion: white light through prism gives VIBGYOR spectrum

Common Mistakes to Avoid
    
      Thinking plane mirror image is real &mdash; it is virtual
      Confusing lateral inversion with upside-down
      Thinking white light is pure &mdash; it is a mixture of 7 colours

Scoring Tips
    
      Draw ray diagrams with incident ray, normal, reflected ray, and angles
      List 5 properties of plane mirror image
      Compare concave and convex mirrors with uses

Question 6

Based on Fig. 11.18, match the position of the torch in Column A with the characteristics of the ball’s shadow in Column B.

Accepted Answer

Column A
Column B

(i) If the torch is close to the ball
(b) The shadow would be larger

(ii) If the torch is far away
(a) The shadow would be smaller

(iii) If the ball is removed from the set-up
(d) A bright spot would appear on the screen

(iv) If two torches are present in the set-up on the left side of the ball
(c) Two shadows would appear on the screen

Chapter 11: Light
    Reflection follows two laws: angle of incidence equals angle of reflection, and all rays are in the same plane. Plane mirror images are virtual, erect, same size, and laterally inverted. Concave mirrors converge light (used in torches, dentist mirrors). Convex mirrors diverge light (used in rear-view mirrors). Dispersion splits white light into VIBGYOR through a prism. Rainbows are natural dispersion by water droplets.
    Theme: Physics | Difficulty: Age-appropriate for Class VII

Key Formulas & Equations

Formula / Equation
        When to Use

Law 1: Angle of incidence = Angle of reflection (&angle;i = &angle;r)First law of reflection
      VIBGYOR: Violet, Indigo, Blue, Green, Yellow, Orange, RedSpectrum colours in order

Must-Know Concepts
  
    Two laws of reflection: &angle;i = &angle;r; same plane
    Plane mirror: virtual, erect, same size, laterally inverted, equal distance behind
    Lateral inversion: left-right swap (AMBULANCE written in reverse)
    Concave mirror: converges light, uses = torch, headlight, dentist, solar cooker
    Convex mirror: diverges light, wider view, uses = rear-view mirror
    Real image: on screen; Virtual image: cannot be on screen
    Dispersion: white light through prism gives VIBGYOR spectrum

Common Mistakes to Avoid
    
      Thinking plane mirror image is real &mdash; it is virtual
      Confusing lateral inversion with upside-down
      Thinking white light is pure &mdash; it is a mixture of 7 colours

Scoring Tips
    
      Draw ray diagrams with incident ray, normal, reflected ray, and angles
      List 5 properties of plane mirror image
      Compare concave and convex mirrors with uses

Question 7

Match the items in Column A with those in Column B.
Column A
Column B
(i) Pinhole
(a) Blocks light completely camera
(ii) Opaque object
(b) The dark region formed behind the object
(iii) Transparent object
(c) Forms an inverted image
(iv) Shadow
(d) Light passes almost completely through it

Accepted Answer

Column AColumn B(i) Pinhole(c) Forms an inverted image(ii) Opaque object(a) Blocks light completely camera(iii) Transparent object(d) Light passes almost completely through it(iv) Shadow(b) The dark region formed behind the object

Chapter 11: Light
    Reflection follows two laws: angle of incidence equals angle of reflection, and all rays are in the same plane. Plane mirror images are virtual, erect, same size, and laterally inverted. Concave mirrors converge light (used in torches, dentist mirrors). Convex mirrors diverge light (used in rear-view mirrors). Dispersion splits white light into VIBGYOR through a prism. Rainbows are natural dispersion by water droplets.
    Theme: Physics | Difficulty: Age-appropriate for Class VII

Key Formulas & Equations

Formula / Equation
        When to Use

Law 1: Angle of incidence = Angle of reflection (&angle;i = &angle;r)First law of reflection
      VIBGYOR: Violet, Indigo, Blue, Green, Yellow, Orange, RedSpectrum colours in order

Must-Know Concepts
  
    Two laws of reflection: &angle;i = &angle;r; same plane
    Plane mirror: virtual, erect, same size, laterally inverted, equal distance behind
    Lateral inversion: left-right swap (AMBULANCE written in reverse)
    Concave mirror: converges light, uses = torch, headlight, dentist, solar cooker
    Convex mirror: diverges light, wider view, uses = rear-view mirror
    Real image: on screen; Virtual image: cannot be on screen
    Dispersion: white light through prism gives VIBGYOR spectrum

Common Mistakes to Avoid
    
      Thinking plane mirror image is real &mdash; it is virtual
      Confusing lateral inversion with upside-down
      Thinking white light is pure &mdash; it is a mixture of 7 colours

Scoring Tips
    
      Draw ray diagrams with incident ray, normal, reflected ray, and angles
      List 5 properties of plane mirror image
      Compare concave and convex mirrors with uses

Question 8

Sahil, Rekha, Patrick, and Qasima are trying to observe the candle flame through the pipe as shown in Fig. 11.16. Who can see the flame?

Accepted Answer

Only Rekha can see the flame of the candle because light travels in a straight line, and Rekha’s line of sight is aligned with the flame. The others cannot see the flame because they are not in the path of the pipe where the flame is visible

Chapter 11: Light
    Reflection follows two laws: angle of incidence equals angle of reflection, and all rays are in the same plane. Plane mirror images are virtual, erect, same size, and laterally inverted. Concave mirrors converge light (used in torches, dentist mirrors). Convex mirrors diverge light (used in rear-view mirrors). Dispersion splits white light into VIBGYOR through a prism. Rainbows are natural dispersion by water droplets.
    Theme: Physics | Difficulty: Age-appropriate for Class VII

Key Formulas & Equations

Formula / Equation
        When to Use

Law 1: Angle of incidence = Angle of reflection (&angle;i = &angle;r)First law of reflection
      VIBGYOR: Violet, Indigo, Blue, Green, Yellow, Orange, RedSpectrum colours in order

Must-Know Concepts
  
    Two laws of reflection: &angle;i = &angle;r; same plane
    Plane mirror: virtual, erect, same size, laterally inverted, equal distance behind
    Lateral inversion: left-right swap (AMBULANCE written in reverse)
    Concave mirror: converges light, uses = torch, headlight, dentist, solar cooker
    Convex mirror: diverges light, wider view, uses = rear-view mirror
    Real image: on screen; Virtual image: cannot be on screen
    Dispersion: white light through prism gives VIBGYOR spectrum

Common Mistakes to Avoid
    
      Thinking plane mirror image is real &mdash; it is virtual
      Confusing lateral inversion with upside-down
      Thinking white light is pure &mdash; it is a mixture of 7 colours

Scoring Tips
    
      Draw ray diagrams with incident ray, normal, reflected ray, and angles
      List 5 properties of plane mirror image
      Compare concave and convex mirrors with uses

Question 9

Look at the images shown in Fig. 11.17 and select the correct image showing the shadow formation of the boy.

Accepted Answer

The boy’s shadow is formed based on the light source. If the light is coming from above, the shadow will fall below. If the light comes from the side, the shadow will be cast in the opposite direction. Thus, option (d) is the correct image showing the shadow formation of the boy.

Chapter 11: Light
    Reflection follows two laws: angle of incidence equals angle of reflection, and all rays are in the same plane. Plane mirror images are virtual, erect, same size, and laterally inverted. Concave mirrors converge light (used in torches, dentist mirrors). Convex mirrors diverge light (used in rear-view mirrors). Dispersion splits white light into VIBGYOR through a prism. Rainbows are natural dispersion by water droplets.
    Theme: Physics | Difficulty: Age-appropriate for Class VII

Key Formulas & Equations

Formula / Equation
        When to Use

Law 1: Angle of incidence = Angle of reflection (&angle;i = &angle;r)First law of reflection
      VIBGYOR: Violet, Indigo, Blue, Green, Yellow, Orange, RedSpectrum colours in order

Must-Know Concepts
  
    Two laws of reflection: &angle;i = &angle;r; same plane
    Plane mirror: virtual, erect, same size, laterally inverted, equal distance behind
    Lateral inversion: left-right swap (AMBULANCE written in reverse)
    Concave mirror: converges light, uses = torch, headlight, dentist, solar cooker
    Convex mirror: diverges light, wider view, uses = rear-view mirror
    Real image: on screen; Virtual image: cannot be on screen
    Dispersion: white light through prism gives VIBGYOR spectrum

Common Mistakes to Avoid
    
      Thinking plane mirror image is real &mdash; it is virtual
      Confusing lateral inversion with upside-down
      Thinking white light is pure &mdash; it is a mixture of 7 colours

Scoring Tips
    
      Draw ray diagrams with incident ray, normal, reflected ray, and angles
      List 5 properties of plane mirror image
      Compare concave and convex mirrors with uses

Question 10

The shadow of a ball is formed on a wall by placing the ball in front of a fixed torch as shown in Fig. 11.18. In scenario (i) the ball is closer to the torch, while in scenario (ii) the ball is closer to the wall. Choose the most accurate representation of the shadows formed in both scenarios from the options provided (a and b).

Accepted Answer

In scenario (i), the ball is closer to the torch and away from the wall, so the shadow would be large and blurry on the wall. So the correct representation of scenario (i) will be (b). In scenario (ii), the ball is closer to the wall and away from the torch, so the shadow would be sharp and small. So the correct representation of scenario (ii) will be (a).

Chapter 11: Light
    Reflection follows two laws: angle of incidence equals angle of reflection, and all rays are in the same plane. Plane mirror images are virtual, erect, same size, and laterally inverted. Concave mirrors converge light (used in torches, dentist mirrors). Convex mirrors diverge light (used in rear-view mirrors). Dispersion splits white light into VIBGYOR through a prism. Rainbows are natural dispersion by water droplets.
    Theme: Physics | Difficulty: Age-appropriate for Class VII

Key Formulas & Equations

Formula / Equation
        When to Use

Law 1: Angle of incidence = Angle of reflection (&angle;i = &angle;r)First law of reflection
      VIBGYOR: Violet, Indigo, Blue, Green, Yellow, Orange, RedSpectrum colours in order

Must-Know Concepts
  
    Two laws of reflection: &angle;i = &angle;r; same plane
    Plane mirror: virtual, erect, same size, laterally inverted, equal distance behind
    Lateral inversion: left-right swap (AMBULANCE written in reverse)
    Concave mirror: converges light, uses = torch, headlight, dentist, solar cooker
    Convex mirror: diverges light, wider view, uses = rear-view mirror
    Real image: on screen; Virtual image: cannot be on screen
    Dispersion: white light through prism gives VIBGYOR spectrum

Common Mistakes to Avoid
    
      Thinking plane mirror image is real &mdash; it is virtual
      Confusing lateral inversion with upside-down
      Thinking white light is pure &mdash; it is a mixture of 7 colours

Scoring Tips
    
      Draw ray diagrams with incident ray, normal, reflected ray, and angles
      List 5 properties of plane mirror image
      Compare concave and convex mirrors with uses

Question 11

Based on Fig. 11.18, match the position of the torch in Column A with the characteristics of the ball’s shadow in Column B.
Column A
Column B
(i) If the torch is close to the ball
(a) The shadow would be smaller
(ii) If the torch is far away
(b) The shadow would be larger
(iii) If the ball is removed from the set-up
(c) Two shadows would appear on the screen
(iv) If two torches are present in the set-up on the left side of the ball
(d) A bright spot would appear on the screen

Accepted Answer

Column AColumn B(i) If the torch is close to the ball(b) The shadow would be larger(ii) If the torch is far away(a) The shadow would be smaller(iii) If the ball is removed from the set-up(d) A bright spot would appear on the screen(iv) If two torches are present in the set-up on the left side of the ball(c) Two shadows would appear on the screen

Chapter 11: Light
    Reflection follows two laws: angle of incidence equals angle of reflection, and all rays are in the same plane. Plane mirror images are virtual, erect, same size, and laterally inverted. Concave mirrors converge light (used in torches, dentist mirrors). Convex mirrors diverge light (used in rear-view mirrors). Dispersion splits white light into VIBGYOR through a prism. Rainbows are natural dispersion by water droplets.
    Theme: Physics | Difficulty: Age-appropriate for Class VII

Key Formulas & Equations

Formula / Equation
        When to Use

Law 1: Angle of incidence = Angle of reflection (&angle;i = &angle;r)First law of reflection
      VIBGYOR: Violet, Indigo, Blue, Green, Yellow, Orange, RedSpectrum colours in order

Must-Know Concepts
  
    Two laws of reflection: &angle;i = &angle;r; same plane
    Plane mirror: virtual, erect, same size, laterally inverted, equal distance behind
    Lateral inversion: left-right swap (AMBULANCE written in reverse)
    Concave mirror: converges light, uses = torch, headlight, dentist, solar cooker
    Convex mirror: diverges light, wider view, uses = rear-view mirror
    Real image: on screen; Virtual image: cannot be on screen
    Dispersion: white light through prism gives VIBGYOR spectrum

Common Mistakes to Avoid
    
      Thinking plane mirror image is real &mdash; it is virtual
      Confusing lateral inversion with upside-down
      Thinking white light is pure &mdash; it is a mixture of 7 colours

Scoring Tips
    
      Draw ray diagrams with incident ray, normal, reflected ray, and angles
      List 5 properties of plane mirror image
      Compare concave and convex mirrors with uses

Question 12

Suppose you view the tree shown in Fig. 11.19 through a pinhole camera. Sketch the outline of the image of the tree formed in the pinhole camera.

Accepted Answer

The formation of image of the tree formed in the pinhole camera is shown.

Source: This question is from Light Shadows and Reflections, Science &mdash; Class 7, CBSE Board.
Key Concepts CoveredThis question tests your understanding of the following concepts from the chapter Light Shadows and Reflections: Suppose, View, Tree, Shown, Fig, Pinhole. These are fundamental topics in Science that students are expected to master as part of the CBSE Class 7 curriculum.A thorough understanding of these concepts will help you answer similar questions confidently in your CBSE examinations. These topics are frequently tested in both objective and subjective sections of Science papers. We recommend revising the relevant section of your textbook alongside practising these solved examples to build a strong foundation.
How to Approach This QuestionRead the question carefully and identify what is being asked. Break down complex questions into smaller parts. Use the terminology and concepts discussed in this chapter. Structure your answer logically — begin with a definition or key statement, then provide supporting details. Review your answer to ensure it addresses all parts of the question completely.
Key Points to RememberRead the question carefully and identify all parts before answering.
Use the terminology specific to this subject and chapter.
Review the textbook content for this chapter before attempting questions.
Practice writing concise, well-structured answers within time limits.
Related Questions from Light Shadows and ReflectionsQ10: The shadow of a ball is formed on a wall by placing the ball in front of a fixed torch as shown in...
Q11: Based on Fig. 11.18, match the position of the torch in Column A with the characteristics of the...
Q13: Write your name on a piece of paper and hold it in front of a plane mirror such that the paper is...
Q14: Measure the length of your shadow at 9 AM, 12 PM, and 4 PM with the help of your friend. Write down...
Q15: On the basis of following statements, choose the correct option. Statement A: Image formed by a...
Practice more questions from Light Shadows and Reflections &mdash; Science, Class 7 CBSE

Chapter 11: Light
    Reflection follows two laws: angle of incidence equals angle of reflection, and all rays are in the same plane. Plane mirror images are virtual, erect, same size, and laterally inverted. Concave mirrors converge light (used in torches, dentist mirrors). Convex mirrors diverge light (used in rear-view mirrors). Dispersion splits white light into VIBGYOR through a prism. Rainbows are natural dispersion by water droplets.
    Theme: Physics | Difficulty: Age-appropriate for Class VII

Key Formulas & Equations

Formula / Equation
        When to Use

Law 1: Angle of incidence = Angle of reflection (&angle;i = &angle;r)First law of reflection
      VIBGYOR: Violet, Indigo, Blue, Green, Yellow, Orange, RedSpectrum colours in order

Must-Know Concepts
  
    Two laws of reflection: &angle;i = &angle;r; same plane
    Plane mirror: virtual, erect, same size, laterally inverted, equal distance behind
    Lateral inversion: left-right swap (AMBULANCE written in reverse)
    Concave mirror: converges light, uses = torch, headlight, dentist, solar cooker
    Convex mirror: diverges light, wider view, uses = rear-view mirror
    Real image: on screen; Virtual image: cannot be on screen
    Dispersion: white light through prism gives VIBGYOR spectrum

Common Mistakes to Avoid
    
      Thinking plane mirror image is real &mdash; it is virtual
      Confusing lateral inversion with upside-down
      Thinking white light is pure &mdash; it is a mixture of 7 colours

Scoring Tips
    
      Draw ray diagrams with incident ray, normal, reflected ray, and angles
      List 5 properties of plane mirror image
      Compare concave and convex mirrors with uses

Question 13

Write your name on a piece of paper and hold it in front of a plane mirror such that the paper is parallel to the mirror. Sketch the image. What difference do you notice? Explain the reason for the difference.

Accepted Answer

When you look at the paper through the plane mirror, the image will be laterally inverted (flipped horizontally). You will notice that the letters of your name appear backward, as the mirror reverses left and right.

Chapter 11: Light
    Reflection follows two laws: angle of incidence equals angle of reflection, and all rays are in the same plane. Plane mirror images are virtual, erect, same size, and laterally inverted. Concave mirrors converge light (used in torches, dentist mirrors). Convex mirrors diverge light (used in rear-view mirrors). Dispersion splits white light into VIBGYOR through a prism. Rainbows are natural dispersion by water droplets.
    Theme: Physics | Difficulty: Age-appropriate for Class VII

Key Formulas & Equations

Formula / Equation
        When to Use

Law 1: Angle of incidence = Angle of reflection (&angle;i = &angle;r)First law of reflection
      VIBGYOR: Violet, Indigo, Blue, Green, Yellow, Orange, RedSpectrum colours in order

Must-Know Concepts
  
    Two laws of reflection: &angle;i = &angle;r; same plane
    Plane mirror: virtual, erect, same size, laterally inverted, equal distance behind
    Lateral inversion: left-right swap (AMBULANCE written in reverse)
    Concave mirror: converges light, uses = torch, headlight, dentist, solar cooker
    Convex mirror: diverges light, wider view, uses = rear-view mirror
    Real image: on screen; Virtual image: cannot be on screen
    Dispersion: white light through prism gives VIBGYOR spectrum

Common Mistakes to Avoid
    
      Thinking plane mirror image is real &mdash; it is virtual
      Confusing lateral inversion with upside-down
      Thinking white light is pure &mdash; it is a mixture of 7 colours

Scoring Tips
    
      Draw ray diagrams with incident ray, normal, reflected ray, and angles
      List 5 properties of plane mirror image
      Compare concave and convex mirrors with uses

Question 14

Measure the length of your shadow at 9 AM, 12 PM, and 4 PM with the help of your friend. Write down your observations:
(i) At which of the given times is your shadow the shortest?
(ii) Why do you think this happens?

Accepted Answer

(i) The shadow will be shortest at 12 PM when the Sun is directly overhead.(ii) This happens because, at 12 PM, the Sun is at its highest point in the sky, so the angle between the Sun and the ground is almost 90 degrees, casting a shorter shadow.

Chapter 11: Light
    Reflection follows two laws: angle of incidence equals angle of reflection, and all rays are in the same plane. Plane mirror images are virtual, erect, same size, and laterally inverted. Concave mirrors converge light (used in torches, dentist mirrors). Convex mirrors diverge light (used in rear-view mirrors). Dispersion splits white light into VIBGYOR through a prism. Rainbows are natural dispersion by water droplets.
    Theme: Physics | Difficulty: Age-appropriate for Class VII

Key Formulas & Equations

Formula / Equation
        When to Use

Law 1: Angle of incidence = Angle of reflection (&angle;i = &angle;r)First law of reflection
      VIBGYOR: Violet, Indigo, Blue, Green, Yellow, Orange, RedSpectrum colours in order

Must-Know Concepts
  
    Two laws of reflection: &angle;i = &angle;r; same plane
    Plane mirror: virtual, erect, same size, laterally inverted, equal distance behind
    Lateral inversion: left-right swap (AMBULANCE written in reverse)
    Concave mirror: converges light, uses = torch, headlight, dentist, solar cooker
    Convex mirror: diverges light, wider view, uses = rear-view mirror
    Real image: on screen; Virtual image: cannot be on screen
    Dispersion: white light through prism gives VIBGYOR spectrum

Common Mistakes to Avoid
    
      Thinking plane mirror image is real &mdash; it is virtual
      Confusing lateral inversion with upside-down
      Thinking white light is pure &mdash; it is a mixture of 7 colours

Scoring Tips
    
      Draw ray diagrams with incident ray, normal, reflected ray, and angles
      List 5 properties of plane mirror image
      Compare concave and convex mirrors with uses

Question 15

On the basis of following statements, choose the correct option.
Statement A: Image formed by a plane mirror is laterally inverted.
Statement B: Images of alphabets T and O appear identical to themselves in a plane mirror.
(i) Both statements are true
(ii) Both statements are false
(iii) Statement A is true, but statement B is false
(iv) Statement A is false, but statement B is true

Accepted Answer

(i) Both statements are true. Plane mirrors create a laterally inverted image (left to right is reversed), and some alphabets like T and O appear the same in a plane mirror.

Source: This question is from Light Shadows and Reflections, Science &mdash; Class 7, CBSE Board.
Key Concepts CoveredThis question tests your understanding of the following concepts from the chapter Light Shadows and Reflections: Basis, Statements, Choose, Correct, Option, Statement. These are fundamental topics in Science that students are expected to master as part of the CBSE Class 7 curriculum.A thorough understanding of these concepts will help you answer similar questions confidently in your CBSE examinations. These topics are frequently tested in both objective and subjective sections of Science papers. We recommend revising the relevant section of your textbook alongside practising these solved examples to build a strong foundation.
How to Approach This QuestionRead the question carefully and identify what is being asked. Break down complex questions into smaller parts. Use the terminology and concepts discussed in this chapter. Structure your answer logically — begin with a definition or key statement, then provide supporting details. Review your answer to ensure it addresses all parts of the question completely.
Key Points to RememberRead the question carefully and identify all parts before answering.
Use the terminology specific to this subject and chapter.
Review the textbook content for this chapter before attempting questions.
Practice writing concise, well-structured answers within time limits.
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Q12: Suppose you view the tree shown in Fig. 11.19 through a pinhole camera. Sketch the outline of the...
Q13: Write your name on a piece of paper and hold it in front of a plane mirror such that the paper is...
Q14: Measure the length of your shadow at 9 AM, 12 PM, and 4 PM with the help of your friend. Write down...
Practice more questions from Light Shadows and Reflections &mdash; Science, Class 7 CBSE

Chapter 11: Light
    Reflection follows two laws: angle of incidence equals angle of reflection, and all rays are in the same plane. Plane mirror images are virtual, erect, same size, and laterally inverted. Concave mirrors converge light (used in torches, dentist mirrors). Convex mirrors diverge light (used in rear-view mirrors). Dispersion splits white light into VIBGYOR through a prism. Rainbows are natural dispersion by water droplets.
    Theme: Physics | Difficulty: Age-appropriate for Class VII

Key Formulas & Equations

Formula / Equation
        When to Use

Law 1: Angle of incidence = Angle of reflection (&angle;i = &angle;r)First law of reflection
      VIBGYOR: Violet, Indigo, Blue, Green, Yellow, Orange, RedSpectrum colours in order

Must-Know Concepts
  
    Two laws of reflection: &angle;i = &angle;r; same plane
    Plane mirror: virtual, erect, same size, laterally inverted, equal distance behind
    Lateral inversion: left-right swap (AMBULANCE written in reverse)
    Concave mirror: converges light, uses = torch, headlight, dentist, solar cooker
    Convex mirror: diverges light, wider view, uses = rear-view mirror
    Real image: on screen; Virtual image: cannot be on screen
    Dispersion: white light through prism gives VIBGYOR spectrum

Common Mistakes to Avoid
    
      Thinking plane mirror image is real &mdash; it is virtual
      Confusing lateral inversion with upside-down
      Thinking white light is pure &mdash; it is a mixture of 7 colours

Scoring Tips
    
      Draw ray diagrams with incident ray, normal, reflected ray, and angles
      List 5 properties of plane mirror image
      Compare concave and convex mirrors with uses

Question 16

Suppose you are given a tube of the shape shown in the Fig. 11.20 and two plane mirrors smaller than the diameter of the tube. Can this tube be used to make a periscope? If yes, mark where you will fix the plane mirrors.

Accepted Answer

Yes, the tube can be used to make a periscope. The mirrors should be placed at a 45° angle inside the tube, facing each other, to reflect light through the tube and give you a view from above or around an obstacle.

Chapter 11: Light
    Reflection follows two laws: angle of incidence equals angle of reflection, and all rays are in the same plane. Plane mirror images are virtual, erect, same size, and laterally inverted. Concave mirrors converge light (used in torches, dentist mirrors). Convex mirrors diverge light (used in rear-view mirrors). Dispersion splits white light into VIBGYOR through a prism. Rainbows are natural dispersion by water droplets.
    Theme: Physics | Difficulty: Age-appropriate for Class VII

Key Formulas & Equations

Formula / Equation
        When to Use

Law 1: Angle of incidence = Angle of reflection (&angle;i = &angle;r)First law of reflection
      VIBGYOR: Violet, Indigo, Blue, Green, Yellow, Orange, RedSpectrum colours in order

Must-Know Concepts
  
    Two laws of reflection: &angle;i = &angle;r; same plane
    Plane mirror: virtual, erect, same size, laterally inverted, equal distance behind
    Lateral inversion: left-right swap (AMBULANCE written in reverse)
    Concave mirror: converges light, uses = torch, headlight, dentist, solar cooker
    Convex mirror: diverges light, wider view, uses = rear-view mirror
    Real image: on screen; Virtual image: cannot be on screen
    Dispersion: white light through prism gives VIBGYOR spectrum

Common Mistakes to Avoid
    
      Thinking plane mirror image is real &mdash; it is virtual
      Confusing lateral inversion with upside-down
      Thinking white light is pure &mdash; it is a mixture of 7 colours

Scoring Tips
    
      Draw ray diagrams with incident ray, normal, reflected ray, and angles
      List 5 properties of plane mirror image
      Compare concave and convex mirrors with uses

Question 17

We do not see the shadow on the ground of a bird flying high in the sky. However, the shadow is seen on the ground when the bird swoops near the ground. Think and explain why it is so.

Accepted Answer

This happens because the Sun’s rays are coming from a high angle when the bird is flying high, making the shadow very small and hard to notice. When the bird is closer to the ground, the angle of the sunlight creates a larger, more noticeable shadow on the ground.Class 7 Light Shadows and Reflections Question Answer (Activities)Activity 11.1: Let Us Investigate (Page 155)Fig. 11.4: Matchbox activity light through holesObservation and conclusion: When all three matchboxes are placed in a straight line, with holes at the same height and properly aligned, the light from the torch passes through all the holes and a bright spot appears on the screen placed on the opposite side. This proves that light travels in a straight line. However, when the holes are not in a straight line, the light cannot pass through, and no spot is seen on the screen.Activity 11.2: Let Us Explore (Page 155)Fig. Viewing candle flame through, (a) a straight pipe (b) a bent pipeObservation and conclusion: We are able to see the candle flame through a straight pipe, as shown in fig. 11.5 (a), but not through a bent pipe, as shown in fig. 11.5 (b), because light travels in a straight line.Activity 11.3: Let Us Experiment (pages 156-157)Fig. Passing light through different materialsTable 11.1: Light through different materialsMaterialCardboardTransparent/Translucent/OpaqueLight will pass fully/partially/not at allMy predictionMy observationPaperOpaqueNot at allNot at allGlassOpaqueNot at allNot at allTracingTransparentFullyFullypaperTranslucentPartiallyPartiallyThick clothOpaqueNot at allNot at allWax paperTranslucentPartiallyPartiallyWaterTransparentFullyFullyObservation and conclusion: Transparent materials allow light to pass through them completely, so we can see clearly through them. Translucent materials allow some light to pass through them, so we can see partially through them. Opaque materials do not allow light to pass through them, so we cannot see through them.Activity 11.4: Let Us Explore (Pages 158-159)Table 11.2: Observation of shadowsActionObservations regarding shadowThe screen is removed.Shadow cannot be seenThe object is removed.No shadow is formedThe torch is switched off.No shadow is formedThe object is moved closer to the screen, keeping the torch and the screen fixed.Shadow becomes smallerThe object is moved closer to the torch, keeping the torch and the screen fixed.Shadow becomes largerThe object is tilted, keeping the torch and the screen fixed.Shape of shadow changesThe colour of the object is changed.Colour of shadow does not changeObservation and conclusion: A shadow is formed when an opaque object blocks the path of light. The source of light, opaque object, and screen are necessary for the formation of a shadow. Changing the colour of the object does not affect the colour of the shadow. The position of the object affects the size and shape of the shadow:If the object is moved closer to the screen, the shadow becomes smaller.If the object is moved closer to the light source, the shadow becomes larger.Tilting the object changes, the shape of the shadow.Activity 11.5: Let Us Investigate (Pages 159-160)Fig. Using mirror to redirect sunlight on a wall.Observation and conclusion: When a shiny flat steel plate or mirror is tilted in different directions, we can see a spot of light on the wall or a nearby surface.When we change the angle of the mirror or plate, the direction of the light also changes. This happens because the shiny surface or mirror changes the direction of the light that falls on it and this change in the direction of light by the mirror or shiny surface is known as reflection of light.Activity 11.6: Let Us Experiment (Page 160)Fig. (a) A light beam (b) Reflection of light in a plane mirror.Observation and conclusion: When a narrow beam of light passes through a small slit and falls on a white sheet, it travels in a straight path, as shown in Fig.(a). However, when a plane mirror is placed in the path of this light beam, the direction of the beam changes, as shown in Fig. (b). This change in the direction of light when it strikes a shiny surface like a mirror is called reflection of light.Activity 11.7: Let Us Experiment (Page 161)Fig. Image of a pen in a plane mirror.Observation and conclusion: In the plane mirror, image is formed behind the mirror and is of the same size as the object. The image formed by a plane mirror is always erect (upright) in nature. However, the image formed by a plane mirror cannot be obtained on the screen.Activity 11.8: Let Us Experiment (Pages 161-162)Fig. Observing one’s own image in a mirror.Observation and conclusion: In a plane mirror, the image is formed at the same distance behind the mirror as the object is in front of it. If the object is closer to the mirror, the image will also be closer. If the object is far from the mirror, the image will also appear far. In a plane mirror, the right appears as left and left appears as right; this is due to lateral inversion.Activity 11.9: Let Us Explore (Page 163)Fig. (a) A simple pinhole camera (b) Image of a candle flame on screen.Observation and conclusion: When we place a lighted candle in the front of a cardboard with a small hole, as shown in fig. (a), the light coming from the flame passes through the hole and forms an inverted (upside-down) image of a candle on the screen behind the cardboard, as shown in fig. (b).Activity 11.10: Let Us Construct (Page 163)Do it yourself.

Chapter 11: Light
    Reflection follows two laws: angle of incidence equals angle of reflection, and all rays are in the same plane. Plane mirror images are virtual, erect, same size, and laterally inverted. Concave mirrors converge light (used in torches, dentist mirrors). Convex mirrors diverge light (used in rear-view mirrors). Dispersion splits white light into VIBGYOR through a prism. Rainbows are natural dispersion by water droplets.
    Theme: Physics | Difficulty: Age-appropriate for Class VII

Key Formulas & Equations

Formula / Equation
        When to Use

Law 1: Angle of incidence = Angle of reflection (&angle;i = &angle;r)First law of reflection
      VIBGYOR: Violet, Indigo, Blue, Green, Yellow, Orange, RedSpectrum colours in order

Must-Know Concepts
  
    Two laws of reflection: &angle;i = &angle;r; same plane
    Plane mirror: virtual, erect, same size, laterally inverted, equal distance behind
    Lateral inversion: left-right swap (AMBULANCE written in reverse)
    Concave mirror: converges light, uses = torch, headlight, dentist, solar cooker
    Convex mirror: diverges light, wider view, uses = rear-view mirror
    Real image: on screen; Virtual image: cannot be on screen
    Dispersion: white light through prism gives VIBGYOR spectrum

Common Mistakes to Avoid
    
      Thinking plane mirror image is real &mdash; it is virtual
      Confusing lateral inversion with upside-down
      Thinking white light is pure &mdash; it is a mixture of 7 colours

Scoring Tips
    
      Draw ray diagrams with incident ray, normal, reflected ray, and angles
      List 5 properties of plane mirror image
      Compare concave and convex mirrors with uses