Class 10 Light Chapter MCQ | 25 PYQ Quiz for CBSE 2025-26

Class 10 Science — Light (Reflection & Refraction)

25 MCQ Practice Quiz (Easy · Moderate · Hard) — Select an option and click Check Answer to reveal the correct option and an explanation. Use Check All to get your score.

Easy

1. The speed of light in a medium is 1.5 × 10⁸ m/s. What is the refractive index of the medium?

A. 1.5 B. 2 C. 3 D. 4

Easy

2. A ray of light strikes a plane mirror at 30° to the normal. What is the angle of reflection?

A. 15° B. 30° C. 45° D. 60°

Easy

3. Which statement is correct for a concave mirror?

A. It always diverges light B. It forms only virtual images C. It can form real or virtual images depending on object position D. It is used as a rear-view mirror

Easy

4. The focal length of a convex lens is 20 cm. What is its power?

A. +5 D B. +2 D C. –5 D D. –2 D

Easy

5. A concave mirror forms a virtual and enlarged image. The object is placed:

A. At infinity B. Beyond centre of curvature C. Between pole and focus D. At centre of curvature

Easy

6. The refractive index of water is ≈1.33. This means:

A. Light is faster in water than in air B. Speed of light in water is lower than in air C. Refraction does not occur in water D. Water is optically rarer than air

Easy

7. A ray of light passes undeviated through which point of a thin lens?

A. Principal focus B. Optical centre C. Any point on lens D. Centre of curvature

Moderate

8. Snell’s law is expressed as:

A. n₁ sin i = n₂ sin r B. n = sin r / sin i C. v = c/n D. i = r

Moderate

9. The mirror formula is:

A. 1/f = 1/v + 1/u B. 1/f = 1/v − 1/u C. f = u + v D. f = uv

Moderate

10. A coin at the bottom of a beaker filled with water seems raised. This is due to:

A. Reflection B. Refraction C. Dispersion D. Scattering

Moderate

11. The refractive index of glass is 1.5. What is the speed of light in glass? (use c = 3×10⁸ m/s)

A. 3.0 × 10⁸ m/s B. 2.0 × 10⁸ m/s C. 1.5 × 10⁸ m/s D. 4.5 × 10⁸ m/s

Moderate

12. When light travels from air into glass, it:

A. Bends away from the normal B. Its speed increases C. Bends towards the normal D. Does not change direction

Hard

13. Focal length of a concave mirror is 20 cm. What is its power? (use sign convention)

A. +5 D B. –5 D C. +0.2 D D. –0.2 D

Hard

14. The phenomenon of splitting white light into seven colours is called:

A. Reflection B. Dispersion C. Scattering D. Interference

Hard

15. A convex lens produces a virtual, erect and enlarged image. Where is the object placed?

A. At infinity B. Between focus and optical centre C. Between focus and lens (i.e., inside focal length) D. At 2F

Moderate

16. Magnification (m) is given by:

A. m = u/v B. m = v/u C. m = hi/ho D. Both B and C

Moderate

17. Critical angle is defined for light going from:

A. Rarer to denser medium B. Denser to rarer medium C. Air to vacuum D. Vacuum to glass

Moderate

18. A concave lens always forms:

A. Real and inverted image B. Virtual and erect image C. Real and erect image D. No image

Hard

19. A plane mirror forms an image that is:

A. Real and inverted B. Virtual and inverted C. Real and erect D. Virtual and erect

Hard

20. The power of a lens depends on:

A. Radius of curvature of surfaces B. Refractive index of lens material C. Thickness (for thick lenses) & shape D. All of the above

Hard

21. Which colour deviates the most in dispersion by a prism?

A. Red B. Yellow C. Violet D. Green

Moderate

22. The magnification formula relating heights and distances is:

A. m = u/v B. m = v/u C. m = hi/ho D. Both B and C

Easy

23. A ray strikes a plane mirror at 35° to the normal. The reflected ray makes an angle of:

A. 35° B. 70° C. 55° D. 145°

Hard

24. Which technology uses total internal reflection to transmit light over long distances?

A. Periscope B. Optical fibres C. Microscope D. Camera

Hard

25. A concave lens has power –2 D. What is its focal length?

A. +50 cm B. –50 cm C. –2 cm D. +2 cm

Prepared for CBSE Class 10 — Light chapter practice. Answers include short explanations to build conceptual clarity.