Page 141 - Innovator's Science-8

B. Fill in the blanks. Observational Skills

1. A ______________ is a mirror with an inwardly curved reflecting surface.
2. A ______________ is a mirror with an outwardly curved reflecting surface.
3. The ______________ is always equal to the _______________.

4. A concaves lens is also called a _____________ lens.
5. A _____________ lens always forms an image that is erect and diminished.

Problem Solving Skills
C. State whether the given statements are True (T) or False (F).
1. Lenses absorb all the light falling on it.

2. A concave mirror can form both erect and inverted images.
3. The incident ray, normal, and reflected ray all lie in the same plane.

4. Convex mirrors are used in torch reflectors.
5. A magnifying glass is made of a concave lens.

D. Short answer type questions. Critical Thinking Skills
1. Why do side-view mirrors of vehicles carry the warning "Objects in mirror are closer than they
appear"?

2. Distinguish between a concave mirror and a convex mirror.
3. Write two uses of convex lenses.
4. State the two laws of reflection.

5. Why does a concave mirror burn paper when sunlight is focused using it?

E. Long answer type questions. Cognitive Skills
1. Explain with diagrams the difference in image formation between concave and convex mirrors.
2. What are lenses? Explain the difference between a convex lens and a concave lens with diagrams.

3. Discuss the uses of concave and convex mirrors in daily life.
4. With the help of an activity, explain how convex and concave lenses affect parallel beams of light.

Project Ideas Exploration

• Describe an ac vity to show that the incident ray, the reflected ray and the normal at the point of
incidence lie in the same plane.

Life Skills Inference

• Suppose you are in a dark room. Can you see objects in the room? Can you see objects outside the
room. Explain.

Enhance your Life Skills Mental Development

• What is the angle of incidence of a ray if the reflected ray is at an
Reflected ray i
angle of 90° to the incident ray? r Incident ray

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