Current and Circuit Symbols

Question 1

What is electric current?

Answer 1

A flow of electrical charge

Electric current can only flow in a complete (closed) circuit with a source of potential difference.

Question 2

What is the unit of current?

Answer 2

Ampere, A

Question 3

What is the relationship between current and a closed loop circuit?

Answer 3

The current has the same value everywhere in the circuit

Question 4

What is potential difference also known as?

Answer 4

Voltage

Question 5

What unit measures potential difference?

Answer 5

Volt, V

Question 6

What is resistance?

Answer 6

Anything that slows the flow of current

Question 7

What is the unit of resistance?

Answer 7

Ohm, Ω

Question 8

What factors determine the current flowing through a component?

Answer 8

Potential difference and resistance of the component

Question 9

How does resistance affect current for a given potential difference?

Answer 9

The greater the resistance, the smaller the current

Question 10

What is the formula for calculating charge (Q) transferred in a circuit?

Answer 10

Q = It

Question 11

If a battery charger passes a current of 2.0 A for 2.5 hours, how much charge is transferred?

Answer 11

18,000 C

Question 12

What does the size of the current represent?

Answer 12

The rate of flow of charge

Question 13

Fill in the blank: The unit of charge is ______.

Answer 13

Coulombs, C

Question 14

True or False: Current can flow without a potential difference.

Answer 14

False

Question 15

What happens to the charge flow when a larger current flows?

Answer 15

More charge passes around the circuit

Question 16

What is the time duration in seconds for 2.5 hours?

Answer 16

9,000 seconds (2.5 * 60 * 60)

Question 17

What is a Cell in electrical terms?

Answer 17

A device that converts chemical energy into electrical energy

Cells are fundamental components in batteries.

Question 18

What is a Battery?

Answer 18

A collection of cells connected together to provide a larger voltage or capacity

Batteries can be rechargeable or non-rechargeable.

Question 19

What does it mean when a Switch is open?

Answer 19

The circuit is incomplete, preventing current from flowing

An open switch interrupts the electrical circuit.

Question 20

What does it mean when a Switch is closed?

Answer 20

The circuit is complete, allowing current to flow

A closed switch enables the flow of electricity.

Question 21

What is a Filament lamp?

Answer 21

A type of lamp that produces light by heating a filament until it glows

Filament lamps are commonly used in household lighting.

Question 22

What is the purpose of a Fuse?

Answer 22

To protect a circuit by breaking the connection if the current is too high

Fuses prevent overheating and potential fires.

Question 23

What does LED stand for?

Answer 23

Light Emitting Diode

LEDs are energy-efficient light sources.

Question 24

What is a Resistor?

Answer 24

A component that resists the flow of electric current

Resistors are used to control voltage and current in circuits.

Question 25

What is a Variable resistor?

Answer 25

A resistor whose resistance can be adjusted ## Footnote Commonly known as a potentiometer.

Question 26

What is the function of an Ammeter?

Answer 26

To measure the current flowing through a circuit ## Footnote Ammeters are connected in series with the circuit.

Question 27

What is the function of a Voltmeter?

Answer 27

To measure the voltage across two points in a circuit ## Footnote Voltmeters are connected in parallel with the circuit.

Question 28

What is a Diode?

Answer 28

A semiconductor device that allows current to flow in one direction only ## Footnote Diodes are used for rectification in power supplies.

Question 29

What does LDR stand for?

Answer 29

Light Dependent Resistor ## Footnote LDRs change resistance based on light intensity.

Question 30

What is a Thermistor?

Answer 30

A temperature-sensitive resistor ## Footnote Thermistors are used in temperature sensing applications.

Question 31

What does the letter A represent in electrical terms?

Answer 31

Current (Amperes) ## Footnote Amperes measure the flow of electric charge.

Question 32

What does the letter V represent in electrical terms?

Answer 32

Voltage (Volts) ## Footnote Volts measure the electric potential difference.

Question 33

Symbol of a Cell

Answer 33

Question 34

Symbol of a Battery

Answer 34

Question 35

Symbol of a Open Switch

Answer 35

Question 36

Symbol of a Closed Switch

Answer 36

Question 37

Symbol of a Filament lamp (bulb)

Answer 37

Question 38

Symbol of a Fuse

Answer 38

Question 39

Symbol of a LED

Answer 39

Question 40

Symbol of a Resistor

Answer 40

Question 41

Symbol of a Variable Resistor

Answer 41

Question 42

Symbol of a Ammeter

Answer 42

Question 43

Symbol of a Voltmeter

Answer 43

Question 44

Symbol of a Diode

Answer 44

Question 45

Symbol of a LDR

Answer 45

Question 46

Symbol of a Thermistor

Answer 46