Olete.in – MCQs, Mock Tests & Government Job Prep | ECAT ECAT Physics Current Electricity Mcq Questions

The current through a metallic conductor is due to the motion of

1. free electrons
2. protons
3. neutrons
4. still under controversy

✅ Correct Answer: 1

Resistance of a conductor depends upon

1. nature of conductor
2. dimension of conductor
3. physical state of the conductor
4. all of above

✅ Correct Answer: 2

A wire having very high value of conductance is said to be

1. very good conductor
2. moderately good conductor
3. an insulator
4. no specific criterion available

✅ Correct Answer: 1

A wire of uniform area of cross-section A length L and resistance R is cut into two parts. Resistivity of each part

1. remains the same
2. is doubled
3. is halved
4. becomes zero

✅ Correct Answer: 1

Production of heat due to an electric current flowing through a conductor is given by

1. Joule effect
2. Joule Thomsons effect
3. Comptons effect
4. Feed back effect

✅ Correct Answer: 1

When same current passes for same time through a thick and thin wire

1. more heat is produced in thick wire
2. more heat is produced in thin wire
3. no heat is produced in wire
4. less heat is produced in thick wire

✅ Correct Answer: 2

Three equal resistors connected in series with a source of e m f together dissipate 10 W of power each. What will be the power dissipated if the same resistors are connected in parallel across the same source of e m f?A. B. 90WC. 100W D. 120W

1. 40 W
2. 90
3. 100
4. 120

✅ Correct Answer: 2

One kilowatt hour is the amount of energy delivered during

1. one second
2. one day
3. one minute
4. one hour

✅ Correct Answer: 4

Thermocouples convert

1. heat energy into electrical energy
2. heat energy into light energy
3. heat energy into mechanical energy
4. mechanical energy into heat energy

✅ Correct Answer: 1

Three bulbs are rating 40W 60W and 100W designed to work on 220V mains. Which bulb will burn most brightly if they are connected in series across 220 V mains?

1. 40 W bulb
2. 60 W blub
3. 100 W blub
4. all will burn equally brightly

✅ Correct Answer: 1

How much heat does a 40 W bulb generates in one hour?

1. 144000J
2. 144J
3. 1.44J
4. 14J

✅ Correct Answer: 1

An immersion heater of 400 watts kept on for 5 hours will consume electrical power of

1. 2KWh
2. 20KWh
3. 6KWh
4. 12KWh

✅ Correct Answer: 1

Resistance of a super conductor is

1. finite
2. infinite
3. zero
4. changes with every conductor

✅ Correct Answer: 3

Resistance of an ideal insulator is

1. infinite
2. zero
3. finite
4. depends upon nature

✅ Correct Answer: 1

Which one is the best material for making connecting wires?

1. iron
2. tungsten
3. silver
4. copper

✅ Correct Answer: 4

Reciprocal of resistivity is called

1. resistance
2. inductance
3. conductivity
4. flexibility

✅ Correct Answer: 3

When 2? 4? and 6? resistor are connected in parallel their resultant equivalent resistance will be

1. 12?
2. 11/12?
3. 12/11?
4. data is insufficient

✅ Correct Answer: 3

Circuit which gives continuously varying potential is called

1. complex network
2. wheat stone bridge
3. potential divider
4. all of above

✅ Correct Answer: 3

Internal resistance is the resistance offered by

1. source of e m f
2. conductor
3. resistor
4. capacitor

✅ Correct Answer: 1

There are three bulbs of 60W 100W and 200W which bulb has thickest filament.

1. 100W
2. 200W
3. 60W
4. all

✅ Correct Answer: 2

The current in the circuit shown in figure - What will be the current in the circuit?

1. 1/45A
2. 1/10A
3. 1/5A
4. 5A

✅ Correct Answer: 2

Resistance between points A and B in the circuit shown in figure is

1. 4?
2. 6?
3. 10?
4. 8?

✅ Correct Answer: 3

A neon flashlight cell with an emf of 1.5V gives a current of 15A when connected directly to an ammeter of resistance 0.04?. Internal resistance of the cell is

1. 0.0004?
2. 0.06?
3. 0.10?
4. 0.13?

✅ Correct Answer: 2

Resistance of a wire on increasing its temperature will

1. increase with rise in temperature
2. decrease with rise in temperature
3. will remain same
4. depends upon altitude of experimentation

✅ Correct Answer: 1

Specific resistance of a wire

1. will depend on its length
2. will depend on its radius
3. will depend on the type of material of the wire
4. None

✅ Correct Answer: 3

An electric iron is marked 20 volts 500W. The units consumed by it in using if for 24 hours will be

1. 12
2. 24
3. 5
4. 1100

✅ Correct Answer: 1

In the following figure the terminal potential is

1. zero
2. 2V
3. 12V
4. 36V

✅ Correct Answer: 1

In liquids and gases the current is due to the motion

1. negative charges
2. positive charges
3. both negative and positive charges
4. neutral particles

✅ Correct Answer: 3

If 1 ampere current flows through 2m long conductor the charge flow through it in 1 hour will be

1. 3600C
2. 7200C
3. 1C
4. 2C

✅ Correct Answer: 1

The graphical representation of Ohms law is

1. hyperbola
2. ellipse
3. parabola
4. straight line

✅ Correct Answer: 4

Which one of the following materials is useful for making bulb filaments?

1. constantan
2. nichrome
3. copper
4. tungsten

✅ Correct Answer: 1

The resistance of a conductor at absolute zero (OK) is

1. zero almost
2. infinite almost
3. no prediction at all
4. may increase or decrease

✅ Correct Answer: 1

Why should a resistance be introduced in a circuit in series deliberately?

1. to increase current
2. to decrease current
3. to control current
4. just to give a good look to circuit

✅ Correct Answer: 2

Electrical energy is measured in

1. watt
2. horse power
3. kilo watt
4. kilowatt hour

✅ Correct Answer: 4

All electrical appliances are connected in parallel to each other between the main line and neutral wire to get

1. same current
2. same current and potential difference
3. different current but same potential difference
4. different current and potential differences

✅ Correct Answer: 3

Electrical energy is converted to heat at the rate of

1. IRt
2. I2R
3. I2Rt
4. Vit

✅ Correct Answer: 2

Which one of the following bulbs has the least resistance?

1. 100 watt
2. 200 watt
3. 300 watt
4. 60 watt

✅ Correct Answer: 3

A fuse is placed in series with the cireuit to protect against

1. high power
2. high voltage
3. high current
4. over heating

✅ Correct Answer: 4

Terminal potential difference of a battery is greater than its emf when

1. the internal resistance of battery is infinite
2. the internal resistance of battery is zero
3. the battery is charged
4. the battery is discharged

✅ Correct Answer: 3