Light chapter Quiz

student does the experiment on tracing the path of a ray of light passing through a rectangular glass slab for different angles of incidence. He can get a correct measure of the angle of incidence and the angle of emergence by following the labelling indicated in figure:

• 1

• 2

• 3

• 4

No matter how far you stand from a spherical mirror, your image appears erect. The mirror may be ………. .

• Concave mirror

• Convex lens

• Diverging Mirror

• Plane mirror

A 10 mm long awl pin is placed vertically in front of a concave mirror. A 5 mm long image of the awl pin is formed at 30 cm in front of the mirror. The focal length of this mirror is

• -20

• -30

• -40

• -60

A ray of light is travelling from a rarer medium to a denser medium. While entering the denser medium at the point of incidence, it

• Goes straight into the second medium

• Bends towards the normal

• Bends away from the normal

• Does not enter at all

If the power of a lens is – 2 D, what is its focal length?

• -50cm

• +100cm

• +50cm

• -100cm

Point object is placed at a distance of 20 cm from a convex mirror of focal length 20 cm. The image will form at:

• At focus

• At the pole

• Behind the mirror

• At infinity

Magnifying power of a concave lens is

• Always <1

• Always > 1

• Can have any value

• Always = 1

The diagrams showing the correct path of the ray after passing through the

• II and III only

• I and II only

• I, II and III

• I, II and IV

A light ray enters from medium A to medium B as shown in figure. The refractive index of medium B relative to A will be

• Greater than unity

• Less than unity

• Equal to unity

• Zero

In torches, search lights and headlights of vehicles the bulb is placed.......

• between the pole and the focus of the reflector

• very near to the focus of the reflector

• between the focus and centre of curvature of the reflector

• at the centre of curvature of the reflector