120 Important Basic Electrical MCQ Question and Answer | PDF Free Download
1.The rating of a fuse wire is always expressed in
- AAmpere-hours
- BAmpere-volts
- CkWh
- DAmperes
2.In a series circuit with unequal resistances
- AThe highest resistance has the most of the current through it
- BThe lowest resistance has the highest voltage drop
- CThe lowest resistance has the highest current
- DThe highest resistance has the highest voltage drop
3.The filament of an electric bulb is made of
- ACarbon
- BAluminium
- CTungsten
- DNickel
4.If a parallel circuit is opened in the main line, the current
- AIncreases in the branch of the lowest resistance
- BIncreases in each branch
- CIs zero in all branches
- DIs zero in the highest resistive branch
5.If a wire conductor of 0.2 ohm resistance is doubled in length, its resistance becomes
- A0.4 ohm
- B0.6 ohm
- C0.8 ohm
- D1.0 ohm
6.Three 60 W bulbs are in parallel across the 60 V power line. If one bulb burns open
- AThere will be heavy current in the main line
- BRest of the two bulbs will not light
- CAll three bulbs will light
- DThe other two bulbs will light
7.Two resistance R1 and R2are connected in series across the voltage source where R2 > R1. The largest drop will be across
- AR2
- BR1
- CEither R1 or R2
- DNone of them
8.A closed switch has a resistance of
- AZero
- BAbout 50 ohms
- CAbout 500 ohms
- DInfinity
9.The hot resistance of the bulb?s filament is higher than its cold resistance because the temperature co-efficient of the filament is
- AZero
- BNegative
- CPositive
- DAbout 2 ohms per degree
10.Heat in a conductor is produced on the passage of electric current due to
- AReactance
- BCapacitance
- CImpedance
- DResistance
11.The insulation on a current carrying conductor is provided
- ATo prevent leakage of current
- BTo prevent shock
- CBoth of above factors
- DNone of above factors
12.The thickness of insulation provided on the conductor depends on
- AThe magnitude of voltage on the conductor
- BThe magnitude of current flowing through it
- CBoth (a) and (b)
- DNone of the above
13.Which of the following quantities remain the same in all parts of a series circuit?
- AVoltage
- BCurrent
- CPower
- DResistance
14.A 40 W bulb is connected in series with a room heater. If now 40 W bulb is replaced by 100 W bulb, the heater output will
- ADecrease
- BIncrease
- CRemain same
- DHeater will burn out
15.An electric filament bulb can be worked from
- ADC supply only
- BAC supply only
- CBattery supply only
- DAll above
16.Resistance of a tungsten lamp _____________ as applied voltage increases
- ADecreases
- BIncreases
- CRemains same
- DNone of the above
17.Electric current passing through the circuit produces
- AMagnetic effect
- BLuminous effect
- CThermal effect and Chemical effect
- DAll above effects
18.If the efficiency of a machine is to be high, what should be low?
- AInput power
- BLosses
- CTrue component of power
- DkWh consumed
19.Two bulbs of 500 W and 200 W rated at 250 V will have resistance ratio as
- A4 : 25
- B25 : 4
- C2 : 5
- D5 : 2
20.Whether circuit may be AC or DC one, following most effective in reducing the magnitude of the current.
- AReactor
- BCapacitor
- CInductor
- DResistor