General Science | Physics | Electric Current

General Science | Physics | Electric Current

Dec 30, 2024 - 16:27 Updated: Dec 30, 2024 - 16:59
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1. Five bulbs each of 100 watt capacity in a tunnel are illuminated continuously for twenty hours. The consumption of electricity will be

One unit
Two units
Ten units
Twenty units

2. If a bulb of 100 watt burns for 10 hours, the expenditure of electricity will be

0-1 unit
1 unit
10 units
100 units

3. An electric bulb of 100 watt is used for 4 hours. The unit of electric energy used is

400
25
4
0.4

4. How many units of electricity will be consumed if you use a 60 watt electric bulb for 5 hours everyday for

12
9
6
3

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

110 W
110 V
440 W
220 W

6. A dynamo which is said to generate electricity actually acts as a

Source of ions
Source of electric charge
Converter of energy
Source of electrons

7. Dynamo is a machine which is used for

Conversion of high voltage to low voltage
Conversion of electrical energy to mechanical energy
Conversion of mechanical energy to electrical energy
Conversion of low voltage to high voltage

8. Turbines and Dyanamos are used to convert which energy to electrical energy?

Chemical energy
Solar energy
Mechanical energy
Moving coil meter

9. When electrical energy is converted into motion

There is no heat loss
Heat loss is 50 percent
Heat loss is 30 percent
Heat loss is 80 percent

10. A device which converts electrical energy into mechanical energy is

Dynamo
Transformer
Electric motor
Inductor

11. A device which converts chemical energy into electrical energy is called

Battery
Motor
Generator
Moving coil meter

12. Electric motors operating at low voltages tend to burn out because

They draw more current which is inversely proportional to the voltage
They draw more current which is inversely proportional to the square root of the voltage
They draw heat proportional to v²
Low voltage sets in electrical discharge

13. Which of the following metals is used as filament in lighting bulbs?

Iron
Molybdenum
Silver
Tungsten

14. The temperature of the filament of lighted electric bulb is generally

100°C to 500°C
1000°C to 1500°C
2000°C to 2500°C
3000°C to 3500°C

15. In a three-pin electrical plug longest pin should be connected to

Ground terminal
Live terminal
Neutral terminal
Any terminal

16. In electric apparatus 'Earth' is used

To reduce the expenditure
Because the apparatus used 3-phase
For safety
In the form of fuse

17. The electric current does not flow between two properly connected charged bodies if they are having

Same charge
Same capacity
Same resistivity
Same potential

18. Which element is the best conductor of electricity?

Silver
Copper
Aluminium
Iron

19. Principle of fuse is

Chemical effect of electricity
Mechanical effect of electricity
Heating effect of electricity
Magnetic effect of electricity

20. A fuse wire is characterized by

Low resistance and high melting point
Low resistance and low melting point
High resistance and low melting point
High resistance and high melting point

21. Fuse wire used for safety of household have

Low melting point
High melting point
High resistance
Both (A) and (C)

22. The filament of a halogen lamp is an alloy of

Tungsten and iodine
Tungsten and bromine
Tungsten and sodium
Molybdenum and sodium

23. Domestic electrical wiring is basically a

Series connection
Parallel connection
Combination of series and parallel connections
Series connection within each room and parallel connective elsewhere

24. A wire with black insulation during electric supply is

Live wire
Earth wire
Neutral wire
Fuse wire

25. Which gas is filled in normal tubelights?

Sodium vapour with argon
Sodium vapour with neon
Mercury vapour with argon
Mercury vapour with neon

26. Full form of C.F.L. is

Compact Fluorescent Lamp
Centrally Fixed Lamp
Chemical Fluorescent Lamp
Condensed Fluorescent Lamp

27. What gases are filled in fluorescent tube?

Neon
Sodium
Mercury
Mercury and neon

28. How does the white light produce in the tube?

To heat up the copper wire
To heat up the filament
To accelerate the atoms
To oscillate molecule

29. Which is the gas inside an electric bulb?

Argon
Nitrogen
Carbon dioxide
Both (A) and (B)

30. Fluorescent tubes are fitted with a choke. The choke coil

Steps up the line voltage
Steps down the line voltage
Reduces current in the circuit
Chokes low frequency current

31. A mobile phone charger is

An inverter
A UPS
A step up transformer
A step down transformer

32. If potential difference and current flowing through a wire is increased twice each, then electric power

Will remain unaffected
Will increase four times
Will increase two times
Will decrease half

33. Two wires have their lengths, diameters and resistivities all in the ratio of 12. If the resistance of the thinner wire is 10 ohm, the resistance of the thicker wire is

5 ohm
10 ohm
20 ohm
40 ohm

34. Transformer is used for

Converting AC into DC
Converting DC into AC
To step up DC voltages
To step up or step down AC voltages

35. Alternate current is not preferable

To charge storage battery
To run/start an electric motor
To transmit electric power
To heat up electric toaster

36. The device used for converting alternating current to direct current is called

Inverter
Rectifier
Transformer
Transmitter

37. Alternating current is converted to direct current

By Dynamo
By Motor
By Transformer
By Rectifier

38. Which of the following option represents the consumption of power in ascending order?

Television, fan, electronic press, electronic kettle
Television, fan, electronic kettle, electronic press
Fan, television, electronic press, electronic kettle
Electronic press, electronic kettle, fan, television

39. The Earth's magnetic field is due to

Currents circulating inside the core
Presence of a huge magnet at its centre
Moving charges in space outside
None of the above

40. Nickel-Cadmium (Ni-Cd) battery is used in

Calculator
Cordless electronic appliances
Transistors
All of the above