electric current and magnetism - Category wise Question and Answer Practice Test with Solutions

Question : 21

The resistivity of a wire depends on

a) area of cross-section

b) material

c) length

d) all of these

Question : 22

The laws of electromagnetic induction have been used in the construction of a

a) voltmeter

b) electric motor

c) galvanometer

d) generator

Question : 23

Lenz’s law is a consequence of the law of conservation of

a) mass

b) energy

c) charge

d) momentum

Question : 24

When a p-n junction diode is reverse biased the flow of current across the junction is mainly due to

a) drift of charges

b) depends on the nature of material

c) diffusion of charges

d) both drift and diffusion of charges

Question : 25 [RAS/RTS (Pre) 2012]

A 100 watt electric bulb is used for 10 hours. What will be the cost of electricity consumed, if the consumption cost is Rs.5 per unit?

a) Rs.25

b) Rs.5

c) Rs.10

d) Rs.50