Page 140 - Innovator's Science-8

ii. Figure (a) indicates a convex mirror and Figure (b) indicates a concave mirror.
iii. Figure (a) indicates a concave mirror and Figure (b) indicates a convex mirror.
iv. Figure (a) indicates a plane mirror, and Figure (b) indicates a convex mirror.
Ans. (ii) Figure (a) indicates a convex mirror and Figure (b) indicates a concave mirror.

12. Place a pencil behind a transparent glass tumbler (Figure a). Now fill the tumbler halfway with water
(Figure b). How does the pencil appear when mewed through the water? Explain why its shape
appears changed.

Ans. When you put a pencil behind a clear glass tumbler and fill it halfway with water, the pencil looks like it's
bent or broken where it goes into the water. The part under the water may also seem a bit thicker or
moved to the side. This happens because light changes direc on when it passes from air into water, a
process called refrac on. Since water slows down and bends the light rays differently than air, your eyes
see the submerged part of the pencil in a shi ed posi on, making it look bent or distorted.

Put on your
Thinking cap Problem Solving Skills

A. Darken the correct options in the OMR Sheet: OMR Sheet

1. Which of the following is a converging lens?
a. Concave lens b. Convex lens
c. Plane glass plate d. Cylindrical glass
Wrong Methods
2. A concave mirror forms an enlarged and erect image when the object is
placed: Correct Method
a. very close to the mirror b. at the centre of curvature

c. at infinity d. at a large distance from the mirror 1. a b c d
3. The angle between the normal and the incident ray is called:
a. angle of reflection b. angle of refraction 2. a b c d

c. angle of incidence d. angle of deviation
4. The image formed by a convex mirror is always: 3. a b c d
a. erect and enlarged b. erect and diminished

c. inverted and diminished d. same size as the object 4. a b c d
5. The side-view mirrors of vehicles are:

a. plane mirrors b. concave mirrors 5. a b c d
c. convex mirrors d. none of these

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