NCERT Light Objective Questions
NCERT Light Objective Questions
Class: 7 |
Subject: Science |
Section: 14 – Light |
Topic: Light MCQs with Answers & Explanations
CBSE Board Examination – Concept Based MCQs
1. What is the main source of natural light on Earth?
Answer: B. Sun
The Sun is the primary natural source of light for Earth. It emits enormous amounts of energy which travel as light and heat. Without sunlight, life would not exist.
The Sun is the primary natural source of light for Earth. It emits enormous amounts of energy which travel as light and heat. Without sunlight, life would not exist.
2. Objects that give out light are called:
Answer: A. Luminous objects
Luminous objects produce their own light, such as the Sun, stars, and electric bulbs.
Luminous objects produce their own light, such as the Sun, stars, and electric bulbs.
3. Which of the following is a non‑luminous object?
Answer: C. Moon
The Moon does not produce its own light. It reflects sunlight, so it is non‑luminous.
The Moon does not produce its own light. It reflects sunlight, so it is non‑luminous.
4. The bouncing back of light from a surface is called:
Answer: B. Reflection
Reflection occurs when light strikes a surface like a mirror and returns to our eyes, enabling us to see images.
Reflection occurs when light strikes a surface like a mirror and returns to our eyes, enabling us to see images.
5. A smooth polished surface forms:
Answer: B. Regular reflection
Smooth surfaces like mirrors reflect light in one direction, producing clear images.
Smooth surfaces like mirrors reflect light in one direction, producing clear images.
6. Which mirror forms a virtual and erect image?
Answer: A. Plane mirror
A plane mirror always forms a virtual, erect, and same‑sized image.
A plane mirror always forms a virtual, erect, and same‑sized image.
7. Periscope works on the principle of:
Answer: B. Reflection
Periscopes use two plane mirrors to reflect light and allow viewing over obstacles.
Periscopes use two plane mirrors to reflect light and allow viewing over obstacles.
8. Which surface scatters light in many directions?
Answer: B. Rough wall
Rough surfaces cause diffused reflection, scattering light.
Rough surfaces cause diffused reflection, scattering light.
9. Image formed by a plane mirror is:
Answer: C. Laterally inverted
Left and right sides appear reversed in plane mirror images.
Left and right sides appear reversed in plane mirror images.
10. Kaleidoscope works on multiple:
Answer: B. Reflections
Multiple mirrors create repeated reflection patterns.
Multiple mirrors create repeated reflection patterns.
11. Shadows are formed when light is:
Answer: B. Blocked
Opaque objects block light, forming shadows.
Opaque objects block light, forming shadows.
12. Transparent objects allow:
Answer: C. Full light
Transparent materials like glass allow most light to pass.
Transparent materials like glass allow most light to pass.
13. Translucent objects allow:
Answer: C. Some light
They allow partial transmission, e.g., butter paper.
They allow partial transmission, e.g., butter paper.
14. Which device uses mirrors to see inside the body?
Answer: B. Endoscope
Endoscopes use reflection to view internal organs.
Endoscopes use reflection to view internal organs.
15. Number of images between two mirrors depends on:
Answer: B. Angle
Smaller angles produce more images due to repeated reflection.
Smaller angles produce more images due to repeated reflection.
16. Concave mirrors are used in:
Answer: B. Shaving mirrors
They produce enlarged images when object is close.
They produce enlarged images when object is close.
17. Convex mirrors give images that are:
Answer: C. Diminished
Convex mirrors form smaller, upright images.
Convex mirrors form smaller, upright images.
18. Rear view mirrors are convex because they:
Answer: B. Show wider area
Convex mirrors provide a larger field of view.
Convex mirrors provide a larger field of view.
19. Which travels fastest?
Answer: B. Light
Light travels at about 3 × 10⁸ m/s, faster than sound.
Light travels at about 3 × 10⁸ m/s, faster than sound.
20. We can see objects due to:
Answer: B. Reflection of light
Light reflected from objects enters our eyes, enabling vision.
Light reflected from objects enters our eyes, enabling vision.