EASY
7th ICSE
IMPORTANT
Earn 100

A Newton's disc can be created by painting a disc with seven different colours, violet, indigo, blue, green, yellow, orange, and red. When the disc is rotated at a high speed, it appears white in colour. Why?

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Important Questions on Light Energy

EASY
7th ICSE
IMPORTANT
Lakhmir Singh's Science Physics>Chapter 4 - Light Energy>Think & Answer>Q 1
Many television sets and computer monitors produce the range of colours on monitor by the use of red, green and blue light emittimg phosphors. Why?
EASY
7th ICSE
IMPORTANT
Lakhmir Singh's Science Physics>Chapter 4 - Light Energy>EXERCISES>Q 2
Which of the following will produce a diffuse reflection of light?
A. Plane mirror
B. Piece of paper
C. Still water in a lake
D. Leather bag
EASY
7th ICSE
IMPORTANT
Lakhmir Singh's Science Physics>Chapter 4 - Light Energy>EXERCISES>Q 3
If you stand 1 m infront of a plane mirror, how far away would you see yourself in the mirror?
EASY
7th ICSE
IMPORTANT
Lakhmir Singh's Science Physics>Chapter 4 - Light Energy>EXERCISES>Q 4
The image formed on plane mirror is:
EASY
7th ICSE
IMPORTANT
Lakhmir Singh's Science Physics>Chapter 4 - Light Energy>EXERCISES>Q 5
Which one of the following is the best reflector of light?
EASY
7th ICSE
IMPORTANT
Lakhmir Singh's Science Physics>Chapter 4 - Light Energy>WORKSHEET>Q A
Draw a diagram showing reflection from a sheet of paper.
EASY
7th ICSE
IMPORTANT
Lakhmir Singh's Science Physics>Chapter 4 - Light Energy>WORKSHEET>Q C
Why do we need a shiny surface for reflection?
EASY
7th ICSE
IMPORTANT
Lakhmir Singh's Science Physics>Chapter 4 - Light Energy>EXERCISES>Q 1

Choose the correct option.

 The angle of incidence on a plane mirror is 30°. The angle of reflection will be: