set 4 MCQ Questions & Answers Detailed Explanation

Question : 1

An oscillator is nothing but an amplifer with

a) negative feedback

b) large gain

c) positive feedback

d) no feedback

Question : 2

An alternating current can be converted into direct current by a

a) transformer

b) dynamo

c) rectifier

d) motor

Question : 3

The energy band gap is minimum in

a) superconductors

b) insulators

c) metals

d) semiconductors.

Question : 4

A mobile phone charger is

a) A step up transformer

b) An inverter

c) A UPS

d) A step down transformer

Question : 5

Fluorescent tubes are fitted with a choke. The choke coil

a) Reduces current in the circuit

b) Steps up the line voltage

c) Steps down the line voltage

d) Chokes low frequency current

Question : 6

An electric bulb is connected to 220 V generator. The current is 0.5A. The power of the bulb is

a) 440 W

b) 110 W

c) 110 V

d) 220 W