Work Power MCQ Questions Answers Electrical Engineering
1) One kilowatt hour is equal to
a) 36 x 103 J
b) 103 J
c) 36 x 105 J
d) 105 J
2) A heater coil rated at 1000 W, 220 V is connected to 110 V line. Power consumed is
a) 250 W
b) 500 W
c) 200 W
d) 400 W
3) A kilowatt hour is the unit of
a) energy
b) power
c) electric charge
d) electric current
4) If current in an electric bulb drops by 2%, then power decreases by
a) 2%
b) 4%
c) 1%
d) 16%
5) A 100 W bulb will give heat and light energy of
a) 100 J/s
b) 200 J/s
c) 50 J/s
d) 150 J/s
6) A fuse wire is made of
a) copper
b) tungsten
c) lead-tin-alloy
d) nichrome
7) Lamps used for house lighting are connected in
a) series
b) parallel
c) mixed grouping
d) arbitrary manner
8) An immersion heater is rated 418 W. It should heat a litre of water from 10oC to 30oC in nearly
a) 100 s
b) 200 s
c) 144 s
d) 400 s
9) By what percentage will the incandescence a lamp decrease if the current drops by 2%?
a) 1%
b) 4%
c) 2%
d) 8%
10) The heater element in an electric iron is made of
a) nichrome
b) iron
c) tungsten
d) constantan