set 4 MCQ Questions & Answers Detailed Explanation

Question : 1

A compass which is allowed to move in a horizontal plane is taken to a geomagnetic pole. It

a) will stay in any position

b) will stay in north-south direction only

c) will stay in east-west direction only

d) None of these

Question : 2

Consider the following statements regarding electric fuse wire:

1. It has low melting point.
2. It has very high specific resistance.
3. It is connected in parallel with the electric circuit.

a) 1 and 2

b) 1 only

c) 1 and 3

d) 2 and 3

Question : 3

If a bulb of 100 watt burns for 10 hours, the expenditure of electricity will be

a) 10 units

b) 0-1 unit

c) 1 unit

d) 100 units

Question : 4

The polarity of an unmarked horse shoe magnet can be determined by using

a) an electroscope

b) a charged glass rod

c) a magnetic compass

d) another unmarked bar magnet

Question : 5

Transformer is used for

a) To step up DC voltages

b) Converting AC into DC

c) Converting DC into AC

d) To step up or step down AC voltages

Question : 6

Refractive index of an optical medium changes with

1. the nature of the medium.
2. the change in the angle of incidence of the ray.
3. colour of the incident ray.

a) 1 and 2 only

b) 1 and 3 only

c) 2 and 3 only

d) 1, 2 and 3