Basic electrical MCQ #1

1) The heating element of electric iron is a combination of which metal,

        a) iron and chromium

        b) nickel and chromium

        c) nickel and copper

        d) copper and magnesium

2) The filters are used to convert _______ signal into a _______ signal.

        a) pulsating DC, pure DC

        b) AC, pulsating DC

        c) pulsating DC, pure AC

        d) pure AC, pulsating DC

3) 3-point starter is used to start in ______ motor?

        a) series

        b) compound

        c) shunt

        d) b & c

4) the synchronous generator is also known as,

        a) alternator

        b) DC generator

        c) AC generator

        d) a & c

5) in a balanced three-phase system, if one of the two wattmeter reading is -ve then the

        a) reading should be taken after reversing the pressure coil

        b) reading should be taken as it is

        c) reading should be taken after reversing the current coil

        d) cannot decide reading

Answer: 1-b|2-a|3-d|4-d|5-a

6) the actual speed of induction motor is always _______ the synchronous speed,

        a) less than

        b) greater than

        c) equal to

        d) cannot predict

7) the fusing current of a fuse is depending on

        a) material & length

        b) length & diameter

        c) material, length & diameter

        d) material & diameter

8) the product of RMS value of current and voltage is called as

        a) reactive power

        b) apparent power

        c) real power

        d) a & c

9) when an ac power is applied to a reactive load, then the system voltage is ____ degree out of phase with the current

        a) 0

        b) 90

        c) 180

        d) 270

10) A vector quantity has

        a) the only direction

        b) the only magnitude

        c) both magnitude and direction

        d) none of above

Answer: 6-a|7-c|8-b|9-b|10-c

11) Gauss law is applicable for

        a) point charge

        b) infinite line charge

        c) infinite sheet charge

        d) all of above

12) the amount of flux density (D) produce in the core is dependent on

        a) number of turns and cross-sectional area of core

        b) current

        c) material of the magnetic core and length of the core

        d) all of these

13) the semiconductors behave ______ at low temperature.

        a) perfect insulator

        b) perfect conductor

        c) none of this

14) the atomic number of silicon and germanium is

        a) 32 & 14

        b) 32 & 15

        c) 14 & 32

        d) 15 & 14

15) the tube of tube light is filled with

        a) fluorescent paste

        b) low-pressure inert gas

        c) mercury

        d) b & C

Answer: 11-d|12-d|13-b|14-d|15-c|