Science · Class 7
Light
Reflection, refraction, dispersion, and human eye basics.
4 sections15–25 min read6 MCQs · 2 examples
Chapter Overview
Light travels in straight lines. This chapter covers laws of reflection, plane and spherical mirrors, image formation, kaleidoscope, and dispersion of white light.
Reflection
- Angle of incidence = angle of reflection
- Plane mirror: virtual, erect, same size, lateral inversion
- Concave mirror: converges light; used in torches, dentists
- Convex mirror: diverges; wider field of view in vehicles
White Light and Dispersion
- White light has seven colours (VIBGYOR)
- Prism disperses white light into spectrum
- Rainbow: dispersion by water droplets
Lenses (Introduction)
- Convex lens converges; concave diverges
- Real images can be formed on screen
Solved Examples
Step-by-step solutions — read each step before checking the final answer.
Mirror image
Why is ambulance lettering reversed?
- 1So drivers see correct word in rear-view mirror
- 2Plane mirror lateral inversion
- 3Readable in mirror
Answer
Lateral inversion in mirrors
Concave mirror
Where is concave mirror used as shaving mirror?
- 1Object close to mirror
- 2Enlarged erect virtual image
- 3Curved inward surface
Answer
Close to mirror for magnified image
Key Points to Remember
- ✓ Periscope uses two plane mirrors
- ✓ Kaleidoscope: multiple reflections
- ✓ Blind spot in eye has no rods/cones
Exam Tips
- • Draw ray diagram for plane mirror image
- • Distinguish concave and convex mirrors
- • Explain rainbow formation
Practice MCQs — Light
Test your understanding with topic-wise multiple choice questions. Explanations appear after each answer.
Question 1 of 6Score: 0/0
Angle of incidence equals: