Page 139 - Ripples SCIENCE 7 - TEJPUR Edition 2024 Answer Key

7. The phenomenon of splitting of white light into its constituent colours is called

................... .
(a) Dispersion of light (b) Reflection of light

(c) Refraction of light (d) All of the above
Ans: (a)

B. Fill in the blanks.

1. ....................... lens is also known as a magnifying glass.
Ans: Convex

2. The inner surface of the reflector of a torch acts as a ....................... mirror.
Ans: concave

3. A prism splits light into ....................... colours.
Ans: seven

4. The change in the direction of light by a mirror is called ....................... of light.

Ans: reflection
5. The outer surface of a flat steel spoon acts as a ....................... mirror.

Ans: convex
6. A ray incident at the pole of a spherical mirror is reflected back, making the same

angle with the ....................... .
Ans: principal axis

7. Dentists use a ....................... mirror to reflect light on a particular tooth.

Ans: concave
8. Newton’s disc has ....................... segments which are painted with different colours

present in the rainbow.
Ans: seven

9. The band of seven colours formed that white light is made up of is called .......................
Ans: spectrum

10. Shops use ....................... mirrors so that their shops looks bigger.

Ans: convex
C. State whether the following statement is true (T) or false (F).

1. A real image cannot be formed on the screen.
2. A convex lens always produces a real image.

3. The image formed in a plane mirror is erect, enlarged and virtual.
4. A prism can be used to spilt light into seven colours.

5. The angle between incident ray and normal ray is called angle of reflection.
6. Rectilinear propagation of light means light travels in a zigzag manner.

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