Class 10 Science Test Paper Chapter 9 Light Reflection and Refraction | CBSE Board | Detailed Solutions & Marking Scheme
Here is your CBSE Board-Level, Competency-Based Question Paper (30 Marks) for:
📘 VEDANT IGNITE TEST SERIES
Class 10 – Physics
Chapter: Light – Reflection and Refraction
Time: 1 Hour | Maximum Marks: 30
🔷 Section A (1 × 7 = 7 Marks)
(5 MCQs + 2 Assertion-Reason)
Q1. A ray of light falls on a mirror at 30°. The angle of reflection will be:
(a) 30° (b) 60° (c) 45° (d) 90°
Q2. Which statement best explains why convex mirrors are used as rear-view mirrors?
(a) They form real images
(b) They give wider field of view
(c) They magnify objects
(d) They invert images
Q3. A beam of parallel rays incident on a concave mirror converges at a point. That point is called:
(a) Pole (b) Focus (c) Centre of curvature (d) Aperture
Q4. The refractive index of a medium increases when:
(a) Speed of light increases
(b) Speed of light decreases
(c) Density decreases
(d) Angle of incidence increases
Q5. A plane mirror forms an image which is:
(a) Real and inverted (b) Virtual and erect
(c) Real and erect (d) Virtual and inverted
Assertion-Reason Questions
Q6.
Assertion (A): A concave mirror can form both real and virtual images.
Reason (R): Nature of image depends on object position.
(a) Both A and R are true and R explains A
(b) Both A and R are true but R does not explain A
(c) A is true, R is false
(d) A is false, R is true
Q7.
Assertion (A): Light bends while entering water from air.
Reason (R): Speed of light changes in different media.
(a) Both A and R are true and R explains A
(b) Both A and R are true but R does not explain A
(c) A is true, R is false
(d) A is false, R is true
🔷 Section B (2 × 4 = 8 Marks)
Q8.
Differentiate between ray and beam of light with examples.
Q9.
State the laws of reflection and explain them using a real-life situation.
(Hint: Use mirror or water surface)
👉 Laws: angle of incidence = angle of reflection
Q10.
Explain why image formed by a plane mirror is laterally inverted. Support with diagram.
Q11.
Define:
(a) Principal focus
(b) Radius of curvature
(c) Focal length
(d) Pole
🔷 Section C (3 × 2 = 6 Marks)
Q12. (Numerical – Mirror Formula)
An object is placed 20 cm in front of a concave mirror of focal length 10 cm.
Find the image distance and nature of image.
👉 Use mirror formula: relation between u, v and f
Q13. (Numerical – Refractive Index)
The speed of light in a medium is (2 \times 10^8) m/s.
Find its refractive index.
👉 Formula: refractive index = speed in vacuum / speed in medium
🔷 Section D (5 × 1 = 5 Marks)
Q14.
Draw ray diagrams and explain image formation in a concave mirror when object is:
At infinity
Between F and C
Also mention nature, size, and position of image.
🔷 Section E (Case Study – 4 Marks)
Q15.
A student observes that when she stands very close to a mirror used in a salon, her face appears enlarged and upright. However, when she moves away, the image becomes inverted.
Based on this, answer the following:
(a) Identify the type of mirror used. (1 mark)
(b) Why does the image become inverted at a distance? (1 mark)
(c) State two uses of this mirror in daily life. (2 marks)
Here is your Detailed Solved Answer Key with CBSE Marking Scheme
(Plain format, easy to copy, proper symbols used)
📘 VEDANT IGNITE TEST SERIES – Answer Key
Class 10 Physics | Light – Reflection & Refraction | Marks: 30
🔷 Section A (1 × 7 = 7 Marks)
Q1. Angle of incidence = 30°
Law: ∠i = ∠r
∴ ∠r = 30°
✅ Answer: (a) 30° (1 mark)
Q2. Convex mirror gives wider field of view → useful for rear-view
✅ Answer: (b) (1 mark)
Q3. Parallel rays converge at focus
✅ Answer: (b) Focus (1 mark)
Q4. Refractive index n = c/v
If v decreases → n increases
✅ Answer: (b) (1 mark)
Q5. Plane mirror → virtual, erect image
✅ Answer: (b) (1 mark)
Q6. Assertion-Reason
A: True (concave mirror forms both images)
R: True (depends on object position)
R explains A
✅ Answer: (a) (1 mark)
Q7. Assertion-Reason
A: True (bending = refraction)
R: True (speed changes in medium)
R explains A
✅ Answer: (a) (1 mark)
🔷 Section B (2 × 4 = 8 Marks)
Q8. Ray vs Beam of Light (2 marks)
Ray: Straight line path of light (imaginary representation)
Beam: Collection of many rays
Examples:
Ray → laser line
Beam → sunlight
Marking Scheme:
Definition (1 mark)
Example (1 mark)
Q9. Laws of Reflection (2 marks)
Angle of incidence = angle of reflection (∠i = ∠r)
Incident ray, reflected ray, normal lie in same plane
Example: Reflection in mirror/water
Marking Scheme:
Laws (1 mark)
Explanation/example (1 mark)
Q10. Lateral Inversion (2 marks)
Left-right interchange in plane mirror
Example: Writing appears reversed
Reason: Image formed behind mirror with reversed orientation
Marking Scheme:
Definition (1 mark)
Explanation/example (1 mark)
Q11. Definitions (2 marks)
(a) Principal Focus (F): Point where parallel rays meet/appear to meet
(b) Radius of Curvature (R): Distance between pole and centre of curvature
(c) Focal Length (f): Distance between pole and focus
(d) Pole (P): Centre of mirror
Marking Scheme:
Any 4 correct definitions → 0.5 × 4 = 2 marks
🔷 Section C (3 × 2 = 6 Marks)
Q12. Mirror Formula Numerical (3 marks)
Given:
u = -20 cm
f = -10 cm
Formula:
1/f = 1/v + 1/u
Substitute:
1/(-10) = 1/v + 1/(-20)
⇒ -1/10 = 1/v - 1/20
⇒ 1/v = -1/10 + 1/20
⇒ 1/v = (-2 + 1)/20
⇒ 1/v = -1/20
∴ v = -20 cm
Nature of Image:
Real (negative v)
Inverted
Same size
Marking Scheme:
Formula (1 mark)
Substitution (1 mark)
Final answer + nature (1 mark)
Q13. Refractive Index Numerical (3 marks)
Given:
c = 3 × 10^8 m/s
v = 2 × 10^8 m/s
Formula:
n = c / v
n = (3 × 10^8) / (2 × 10^8)
n = 3/2 = 1.5
Answer: n = 1.5
Marking Scheme:
Formula (1 mark)
Calculation (1 mark)
Final answer (1 mark)
🔷 Section D (5 × 1 = 5 Marks)
Q14. Concave Mirror Ray Diagrams (5 marks)
Case 1: Object at infinity
Image at focus (F)
Real, inverted, highly diminished
Case 2: Object between F and C
Image beyond C
Real, inverted, enlarged
Marking Scheme:
Diagram (2 marks)
Case 1 explanation (1.5 marks)
Case 2 explanation (1.5 marks)
🔷 Section E (Case Study – 4 Marks)
Q15.
(a) Concave mirror (1 mark)
(b)
At larger distance → object beyond focus → image becomes real & inverted (1 mark)
(c) Uses: (Any 2)
Shaving mirror
Dentist mirror
Reflectors in torches
(1 mark each = 2 marks)
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