# NCERT Class VII Science Solutions: Chapter 15 – Light Part 2

Question 9:

The image formed by a lens is always virtual, erect and smaller in size for an object kept at different positions in front of it. Identify the nature of the lens.

Concave lens.

Question 10:

Fill in the blanks:

1. The inner surface of a steel spoon acts as a ________ mirror.

2. The outer surface of a flat steel plate acts as a _________ mirror.

3. The outer shining surface of a round bottom steel bowl acts as a __________ mirror.

4. The inner surface of the reflector of a torch acts as a _________ mirror.

1. The inner surface of a steel spoon acts as a concave mirror.

2. The outer surface of a flat steel plate acts as a plane mirror.

3. The outer shining surface of a round bottom steel bowl acts as a convex mirror.

4. The inner surface of the reflector of a torch acts as a concave mirror.

Question 11:

State whether the following statements are true or false.

1. A concave lens can be used to produce an enlarged and erect image.

2. A convex lens always produces a real image.

3. The sides of an object and its image formed by a concave mirror are always interchanged.

4. An object can be seen only if it emits light.

1. A concave lens can be used to produce an enlarged and erect image. (False)

2. A convex lens always produces a real image. (False)

3. The sides of an object and its image formed by a concave mirror are always interchanged. (True)

4. An object can be seen only if it emits light. (False)

Question 12:

What type of mirror is used as a side mirror in a scooter? Why is this type of mirror chosen?

Convex mirror. Convex mirrors can form images of objects spread over a large area. So these help the drivers to see the traffic of a large area behind them.

Question 13:

Observe the figures given as Figure carefully.

The given figures show the path of light through lenses of two different types, represented by rectangular boxes A and B. What is the nature of lenses A and B?