Electricity Fundamentals: Master Electric Phenomena with Interactive Quizzes

Question 1

After a capacitor is charged and disconnected from a battery, what occurs to the electric field within it?

Accepted Answer

Remains constant

Answer

Increases

Answer

Decreases

Answer

Becomes zero

Question 2

In a series circuit, what is true about the current through each resistor?

Accepted Answer

Equal to the total current in the circuit

Answer

Different for each resistor

Answer

Inversely proportional to the resistance of the resistor

Answer

Directly proportional to the voltage across the resistor

Question 3

Which of the following does NOT influence the resistance of a conductor?

Accepted Answer

Intensity of magnetic field

Answer

Length

Answer

Cross-sectional area

Answer

Temperature

Question 4

What is the SI unit of electric potential?

Accepted Answer

Volt

Answer

Coulomb

Answer

Henry

Answer

Ohm

Question 5

Which factor does NOT influence the resistance of a wire?

Accepted Answer

Voltage

Answer

Length

Answer

Cross-sectional area

Answer

Material

Question 6

A capacitor stores energy when charged. Its capacitance is C, and the voltage across its plates is V. Which of the following equations correctly expresses the energy W stored in the capacitor?

Accepted Answer

W = 1/2 CV^2

Answer

W = CV

Answer

W = CV^3

Answer

W = 1/4 CV^2

Question 7

Which component in an electrical circuit stores energy by creating a magnetic field when current passes through it?

Accepted Answer

Inductor

Answer

Capacitor

Answer

Resistor

Answer

Transistor

Question 8

Which factor does NOT influence the resistance of a wire?

Accepted Answer

Voltage

Answer

Length

Answer

Cross-sectional area

Answer

Temperature

Question 9

Which of the following describes the relationship between electric potential and electric field strength?

Accepted Answer

Electric potential is related to electric field strength by the equation V = -∫E·dr.

Answer

Electric potential is a scalar quantity that is positive at all points in space.

Answer

Electric potential is a vector quantity that points in the direction of the electric field.

Answer

Electric potential is independent of the charge distribution that creates it.

Question 10

Which of these factors does NOT affect the capacitance of a capacitor?

Accepted Answer

Temperature

Answer

Distance between the plates

Answer

Area of the plates

Answer

Material between the plates

Question 11

Calculate the electric potential (V) at a point located at a distance (r) from a point charge (Q) in free space.

Accepted Answer

V = Q / (4πε₀r)

Answer

V = Qr

Answer

V = Q / r²

Answer

V = Qr²

Question 12

Which of the following is NOT a type of capacitor used in electronic circuits?

Accepted Answer

Resistor

Answer

Ceramic capacitor

Answer

Electrolytic capacitor

Answer

Film capacitor

Question 13

In electricity, what unit is used to measure the difference in electric potential between two points?

Accepted Answer

Volt

Answer

Ampere

Answer

Farad

Answer

Coulomb

Question 14

Which factor does NOT influence the capacitance of a parallel-plate capacitor?

Accepted Answer

Voltage across the plates

Answer

Plate area

Answer

Plate separation

Answer

Material permittivity

Question 15

What is the relationship between electric potential and electric field?

Accepted Answer

Electric potential is the negative gradient of electric field.

Answer

Electric potential is the dot product of electric field and displacement.

Answer

Electric potential is the scalar product of electric field and distance.

Question 16

A capacitor with a capacitance of 100 microfarads (μF) is connected to a battery with a voltage of 12 volts (V). What is the magnitude of the charge stored in the capacitor?

Accepted Answer

1.2 Coulombs (C)

Answer

12 milliCoulombs (mC)

Answer

120 Coulombs (C)

Answer

12 kiloVolts (kV)

Question 17

Which of the following factors does NOT directly affect the resistance of a metal wire?

Accepted Answer

Voltage

Answer

Length

Answer

Cross-sectional area

Answer

Material

Question 18

In a transformer, the primary and secondary coils are wound on a laminated iron core. Why is a laminated iron core used?

Accepted Answer

To reduce eddy currents in the core

Answer

To minimize copper losses in the core

Answer

To enhance the magnetic permeability of the core

Answer

To provide electrical insulation between the coils

Question 19

In a transformer, the ratio of the number of turns in the primary coil to the number of turns in the secondary coil is called the turns ratio. What happens when the turns ratio is increased?

Accepted Answer

The voltage across the secondary coil increases.

Answer

The voltage across the primary coil increases.

Answer

The voltage across the secondary coil decreases.

Answer

The current through the primary coil decreases.

Question 20

In a simple circuit with a battery, a resistor, and an LED, which component's main purpose is to control the current flow?

Accepted Answer

Resistor

Answer

Battery

Answer

LED

Question 21

An electric field is generated by a stationary point charge. Which of the following factors does NOT influence the strength of the electric field at a given point in space created by that charge?

Accepted Answer

Presence of other conductors in the vicinity

Answer

Magnitude of the charge

Answer

Distance from the charge

Question 22

In an electric field, a stationary charged particle experiences a force due to:

Accepted Answer

The electric field gradient

Answer

The magnetic field gradient

Answer

The potential difference

Answer

The current flowing through the particle

Question 23

Which of the following is the SI unit of electric potential difference?

Accepted Answer

Volt

Answer

Ampere

Answer

Ohm

Answer

Farad

Question 24

A circuit containing a battery and a resistor is connected in series. If the resistance of the resistor increases, the current in the circuit:

Accepted Answer

Decreases

Answer

Increases

Answer

Remains the same

Answer

Fluctuates

Question 25

The magnetic field around a current-carrying wire is:

Accepted Answer

Circular

Answer

Radial

Answer

Linear

Answer

Quadratic

Question 26

An inductor is a component that stores energy in its:

Accepted Answer

Magnetic field

Answer

Electric field

Answer

Gravitational field

Answer

Chemical potential

Question 27

When a capacitor is fully charged, the charge on its plates is:

Accepted Answer

Equal but opposite

Answer

Zero

Answer

Equal and of the same sign

Answer

Proportional to the voltage across it

Question 28

The power dissipated in a resistor is given by:

Accepted Answer

P = I^2R

Answer

P = VI

Answer

P = V^2/R

Answer

P = V - I

Question 29

A transformer is used to:

Accepted Answer

Change the voltage and current of an AC supply

Answer

Convert AC to DC

Answer

Convert DC to AC

Answer

Store electrical energy

Question 30

The displacement current in a capacitor is caused by:

Accepted Answer

Change in the electric field inside the capacitor

Answer

Movement of charges in the capacitor

Answer

Flow of current through the capacitor plates

Answer

Change in the magnetic field around the capacitor

Question 31

A positively charged particle moves through a region with a uniform magnetic field. If the strength of the magnetic field is doubled, what happens to the particle's acceleration?

Accepted Answer

Acceleration doubles

Answer

Acceleration halves

Answer

Acceleration stays the same

Answer

Acceleration quadruples

Question 32

Which element in a circuit opposes the flow of electric current?

Accepted Answer

Resistor

Answer

Capacitor

Answer

Inductor

Answer

Diode

Question 33

The relationship between voltage (V), current (I), and resistance (R) in a circuit is described by:

Accepted Answer

Ohm's Law: V = IR

Answer

Kirchhoff's Law

Answer

Faraday's Law

Answer

Lenz's Law

Question 34

What is responsible for the force between electrically charged particles?

Accepted Answer

Electric field

Answer

Magnetic field

Answer

Gravitational field

Answer

Strong nuclear force

Question 35

When an electric charge is in motion, it creates a:

Accepted Answer

Magnetic field

Answer

Electric field

Answer

Gravitational field

Answer

No field is created.

Question 36

What does a capacitor primarily store?

Accepted Answer

Electric charge

Answer

Magnetic flux

Answer

Kinetic energy

Answer

Potential energy

Question 37

The SI unit of capacitance is the:

Accepted Answer

Farad (F)

Answer

Henry (H)

Answer

Ohm (Ω)

Answer

Volt (V)

Question 38

The direction of an electromotive force (EMF) generated by electromagnetic induction is determined by:

Accepted Answer

Lenz's Law

Answer

Right-hand rule

Answer

Gauss's Law

Answer

Ampere's Law

Question 39

Which of the following is the SI unit of electric field strength?

Accepted Answer

Volt per meter

Answer

Coulomb

Answer

Newton

Answer

Ohm

Question 40

What is the relationship between the electric field strength (E) and electric potential (V)?

Accepted Answer

E = - dV/dx

Answer

E = dV/dx

Answer

E = dV/dt

Answer

E = - dt/dV

Question 41

Which of the following materials has a high electrical conductivity?

Accepted Answer

Copper

Answer

Wood

Answer

Plastic

Answer

Glass

Question 42

What is the effect of increasing the resistance in a circuit?

Accepted Answer

Decrease current

Answer

Increase current

Answer

Increase voltage

Answer

Decrease voltage

Question 43

A transformer has 100 turns on the primary coil and 50 turns on the secondary coil. If the primary voltage is 240 V, what is the secondary voltage?

Accepted Answer

120 V

Answer

60 V

Answer

180 V

Answer

240 V

Question 44

Which of the following is considered a magnetic material?

Accepted Answer

Iron

Answer

Aluminum

Answer

Wood

Answer

Paper

Question 45

Which of the following is NOT a factor affecting the EMF of a battery?

Accepted Answer

Coil resistance

Answer

Number of cells

Answer

Concentration of electrolyte

Answer

Temperature

Question 46

Which of the following is a vector quantity?

Accepted Answer

Electric field strength

Answer

Electric potential

Answer

Capacitance

Answer

Resistance

Question 47

Which of the following materials allows electric current to flow through it easily?

Accepted Answer

Copper

Answer

Rubber

Answer

Plastic

Answer

Glass

Question 48

In the International System of Units (SI), what is the unit of electric current?

Accepted Answer

Ampere

Answer

Volt

Answer

Ohm

Answer

Coulomb

Question 49

What is the formula for calculating the energy (E) stored in a capacitor?

Accepted Answer

E = 1/2 CV^2

Answer

E = CV

Answer

E = 1/2 QV

Answer

E = Q^2/2C

Question 50

Which of the following materials is classified as magnetic?

Accepted Answer

Iron

Answer

Aluminium

Answer

Copper

Answer

Gold

Question 51

In a magnetic field, what is the direction of the force exerted on a current-carrying conductor?

Accepted Answer

Perpendicular to both the current and the magnetic field

Answer

Parallel to the current

Answer

Parallel to the magnetic field

Answer

Zero

Question 52

What is the primary function of a transformer?

Accepted Answer

To increase or decrease the voltage of an alternating current

Answer

To convert alternating current to direct current

Answer

To store electrical energy

Answer

To generate an electric current

Question 53

Which of the following devices is used to measure the power dissipated in an electrical circuit?

Accepted Answer

Wattmeter

Answer

Ammeter

Answer

Voltmeter

Answer

Ohmmeter

Question 54

Which of the following is the SI unit of electric charge?

Accepted Answer

Coulomb

Answer

Volt

Answer

Ampere

Answer

Ohm

Question 55

What is the relationship between electric field strength and electric potential?

Accepted Answer

Electric field strength is proportional to the negative gradient of electric potential.

Answer

Electric field strength is inversely proportional to the electric potential.

Answer

Electric field strength is equal to the electric potential.

Answer

Electric field strength is perpendicular to the electric potential.

Question 56

In a series circuit, the total resistance is:

Accepted Answer

Equal to the sum of the individual resistances.

Answer

Less than the largest individual resistance.

Answer

Greater than the largest individual resistance.

Answer

Equal to the smallest individual resistance.

Question 57

Which of the following is NOT a factor that affects the magnetic field of a current-carrying wire?

Accepted Answer

Shape of the wire

Answer

Current in the wire

Answer

Length of the wire

Answer

Distance from the wire

Question 58

What is Lenz's law?

Accepted Answer

The direction of the induced current is such that it opposes the change in magnetic flux.

Answer

The induced current is proportional to the rate of change of magnetic flux.

Answer

The induced current is inversely proportional to the strength of the magnetic field.

Answer

The induced current is independent of the magnetic field.

Question 59

A resistor with a resistance of 10 ohms is connected to a battery with an emf of 12 volts. What is the current flowing through the resistor?

Accepted Answer

1.2 A

Answer

0.8 A

Answer

12 A

Answer

120 A

Question 60

What is the power dissipated in a resistor?

Accepted Answer

I^2R

Answer

VI

Answer

V^2/R

Answer

P=0

Question 61

What is the function of a diode?

Accepted Answer

To allow current to flow in one direction only

Answer

To increase the voltage across a circuit

Answer

To store charge

Answer

To act as a resistor

Question 62

Which of the following is NOT a source of electromagnetic radiation?

Accepted Answer

Sound waves

Answer

Stars

Answer

Microwaves

Answer

Electrical wires

Question 63

The SI unit of electric charge is:

Accepted Answer

Coulomb

Answer

Ampere

Answer

Volt

Answer

Ohm

Question 64

According to Ohm's Law, the voltage drop across a resistor is directly proportional to the:

Accepted Answer

Current flowing through it

Answer

Resistance of the resistor

Answer

Length of the resistor

Answer

Cross-sectional area of the resistor