set 5 MCQ Questions & Answers Detailed Explanation

Question : 1

Match list-I with list -II:

a) 2 1 4 3

b) 3 1 4 2

c) 3 4 1 2

d) 2 4 1 3

Question : 2

Which one among the following is the correct order of power consumption for light of equal intensity ?

a) CFL tube < Fluorescent tube < Light emitting diode < Incandescent bulb

b) CFL tube < Fluorescent tube < Incandescent bulb < Light emitting diode

c) Light emitting diode < CFL tube < Fluorescent tube < Incandescent bulb

d) Incandescent bulb < Light emitting diode < Fluorescent tube < CFL tube

Question : 3

At magnetic poles, the angle of dip is

a) zero

b) 45°

c) 30°

d) 90°

Question : 4

Graphene is frequently in news recently. What is its importance?

1. It is a two-dimensional material and has good electrical conductivity.
2. It is one of the thinnest but strongest materials tested so far.
3. It is entirely made of silicon and has high optical transparency.
4. It can be used as ‘conducting electrodes’ required for touch screens, LCDs and organic LEDs.

a) 1, 2 and 4 only

b) 1 and 2 only

c) 3 and 4 only

d) 1, 2, 3 and 4

Question : 5

Consider the following statements. An ordinary light bulb has a rather short life because the

1. Filament wire is not uniform.
2. Bulb cannot be evacuated completely.
3. Wires supporting the filament melt at high temperatures.

a) 1 and 3

b) 1 and 3

c) 2 and 3

d) 1, 2 and 3

Question : 6

The Donor level in a semiconductor is placed

a) in the forbidden energy gap close to the upper edge of the valence band

b) in the conduction band close to the lower edge to the conduction band

c) half-way in the forbidden energy gap

d) in the forbidden energy gap close to the lower edge of the conduction band