set 7 MCQ Questions & Answers Detailed Explanation

Question : 1

Which element is the best conductor of electricity?

a) Aluminium

b) Silver

c) Copper

d) Iron

Question : 2

Barrier potential of a p-n junction diode does not depend on

a) diode design

b) temperature

c) doping density

d) forward bias

Question : 3

The main power supply in India is at 220 V, whereas that in the US is at 110 V. Which one among the following statements in this regard is correct?

a) 110 V leads to lower power loss

b) 110 V is safer but more expensive to maintain

c) 110 V is safer and cheaper to maintain

d) 110 V works better at higher latitudes

Question : 4

A ray of ligh is incident normally on one of the faces of right angled isosceles prism as shhown above. It undergoes total internal reflection from hypotenuse. Which one of the following is the minimum refractive index of the material of the prism?

a) 1.414

b) 1.0

c) 1.33

d) 1.6

Question : 5

The length of a wire is doubled and the radius is doubled. By what factor does the resistance change?

a) Twice as large

b) Unchanged

c) 4 times as large

d) Half as large

Question : 6

Out of the following, diamagnetic substance is

a) lead

b) iron

c) copper

d) silver