Circuit symbols (SP10a)

Summary

In this engaging GCSE Physics Explained video, viewers are introduced to the names, symbols, and functions of various electrical components used in circuits. The presenter creatively explains the roles of a cell and a battery in providing energy and creating current, the function of a switch in controlling current flow, and the purpose of a voltmeter and ammeter in measuring voltage and current, respectively. The video also covers resistors, variable resistors, bulbs, motors, diodes, thermistors, LDRs, LEDs, and fuses, using analogies and mnemonic devices to make learning the symbols and their uses easier. The presenter encourages learning through creative strategies and promises more educational 3D animations in future videos.

Takeaways

• 🔋 A Cell is a source of electrical energy that pushes electrons around a circuit to create current, with the larger side being positive and the smaller side negative.
• 🔋 A Battery is a collection of cells connected in series, providing a larger amount of electrical energy to produce bigger currents.
• 🔧 A Switch controls the flow of current in a circuit, with a closed switch allowing current to flow and an open switch stopping it.
• 📊 A Voltmeter measures voltage or potential difference, represented by a circle with a 'V' in it.
• 🔌 An Ammeter measures current, symbolized by a circle with an 'A' in it.
• ⛔️ Resistors limit the flow of electrical current, symbolized by a rectangle.
• 🔄 Variable Resistors allow for the adjustment of resistance to control the electrical current, indicated by an 'R' through the rectangle.
• 💡 Bulbs convert electrical energy into light energy, with two symbols: a circle with a cross or an 'L' in the middle, due to their high resistance and glowing property.
• 🔌 Motors convert electrical energy into kinetic energy, represented by a circle with an 'M' in the middle.
• 🚫 A Diode allows current to flow in only one direction, symbolized by an arrow with a line blocking the reverse flow.
• 🌡️ Thermistors are heat sensors that change their resistance with temperature, symbolized by a thermometer-like shape through a resistor.
• 🔆 An LDR (Light Dependent Resistor) is a light sensor that changes resistance with light levels, symbolized by a rectangle in a protective bubble, changing resistance with sunlight.
• 💡 LED stands for Light Emitting Diode, which emits light when current flows in the forward direction, symbolized by a diode with arrows representing light.

Q & A

What is the primary function of a cell in an electrical circuit?

A cell provides electrical energy to push electrons around a circuit and create current. The larger side of the cell is the positive side, and the smaller side is the negative side.

How does a battery differ from a single cell?

A battery is a collection of cells joined together in series, with the negative end of one cell connected to the positive end of the next. This configuration provides a larger amount of electrical energy to push electrons around a circuit and produces bigger currents.

What is the role of a switch in an electrical circuit?

A switch allows or stops the flow of electrical current. A closed switch permits the current to flow, while an open switch stops the current from flowing.

What does a voltmeter measure in an electrical circuit?

A voltmeter measures voltage, which is sometimes referred to as potential difference.

How is a variable resistor different from a fixed resistor?

A variable resistor allows the size of the resistance to be changed, enabling the adjustment of the electrical current to be larger or smaller. The symbol for a variable resistor is a rectangle with an 'R' through it on an angle.

What is the purpose of a bulb in an electrical circuit?

Bulbs are designed to convert electrical energy into light energy. They can be represented by two symbols: a circle with a cross in the middle or a circle with an alms ein in the middle.

What is the symbol for a motor, and what does it represent?

The symbol for a motor is a circle with an 'M' in the middle. It represents the conversion of electrical energy into kinetic energy.

How does a diode function in an electrical circuit?

A diode allows current to flow in only one direction - the forward direction. It has a symbol that looks like an arrow pointing in the direction of current flow with a blocker at the front to prevent current flow in the reverse direction.

What is a thermistor and how does it differ from a regular resistor?

A thermistor is a resistor that changes its resistance as the temperature changes. It is used as a heat sensor. Its symbol resembles a thermometer going through a resistor at an angle.

How does an LDR (Light Dependent Resistor) work, and what is its symbol?

An LDR is a light sensor that changes its resistance when the light changes. Its symbol starts with a normal resistor, represented as a rectangle, but it is enclosed in a protective bubble to symbolize its waterproof nature when placed in environments like lampposts.

What is an LED and how does it differ from a standard diode?

An LED stands for Light Emitting Diode. It is a diode that emits light when current is flowing in the forward direction and does not emit light when current is trying to flow in the reverse direction. Its symbol is a diode symbol with arrows representing light coming out of it.

What is the purpose of a fuse in an electrical circuit?

A fuse is designed to protect a circuit by breaking it if too much current flows through, which could be caused by a faulty electrical appliance. The symbol for a fuse is similar to a halt sign, indicating its role in stopping the flow of current.

Outlines

00:00

🔋 Basics of Electrical Components and Their Symbols

This paragraph introduces the fundamental electrical components used in circuits and their symbolic representations. It explains that a cell provides energy to push electrons and create current, with the positive side marked by a '+' and the negative by a '-'. A battery is described as a series of cells to provide more energy. Switches are depicted as Harry Potter's glasses, open or closed to control the flow of current. Voltage and current are measured with voltmeters and ammeters, respectively. Resistors are highlighted as components that restrict current flow, with variable resistors symbolized by an 'R' through a rectangle. Bulbs are explained as devices converting electrical energy into light, with two possible symbols provided. Motors are mentioned as converting electrical energy into kinetic energy, symbolized by a circle with an 'M'. Diodes are one-way current conductors, symbolized by an arrow with a blocker, and thermistors are heat sensors with resistance that changes with temperature, symbolized like a thermometer through a resistor. An LDR, a light sensor resistor, is also introduced, changing resistance with light exposure.

05:02

💡 Advanced Electrical Components and Their Applications

The second paragraph delves into more complex electrical components and their functions. It starts by discussing the LDR, a light-dependent resistor, which is encapsulated in a protective bubble to make it waterproof, and its resistance changes with sunlight exposure. LED stands for light-emitting diode, which is a diode that emits light when current flows in the forward direction. The symbol for an LED is a diode with arrows representing light emission. Fuses are explained as safety devices that prevent excessive current in a circuit by breaking when too much current flows, symbolized by a thin wire inside a casing. The video concludes with a promise of more 3D animations in future videos and an encouragement to subscribe to the GCSE Physics Explained channel for educational content.

Keywords

💡Cell

A 'Cell' in the context of the video refers to a basic unit that provides electrical energy by pushing electrons around a circuit to create current. It is fundamental to the operation of electrical circuits, as it is the source of power. The video mentions the positive and negative sides of the cell, with the larger side being positive and the smaller side being negative, which is crucial for understanding how cells function within a circuit.

💡Battery

A 'Battery' is described as a collection of cells joined together in series. It is used to provide a larger amount of electrical energy, which is essential for pushing electrons around a circuit and producing larger currents. The video script uses the analogy of a battery being like a group of cells working together, which helps to illustrate the concept of how batteries amplify the power provided by individual cells.

💡Switch

A 'Switch' is depicted as a device that controls the flow of electrical current in a circuit. The video uses the creative analogy of Harry Potter's glasses to describe a closed switch, allowing current to flow, and broken glasses to symbolize an open switch, which stops the current. This keyword is central to the video's theme as it explains how electrical circuits can be controlled.

💡Voltmeter

A 'Voltmeter' is an instrument used to measure voltage, also known as potential difference. The video script describes its symbol as a circle with a 'V' in it. It is a key component in understanding and diagnosing electrical circuits, as it helps measure the electrical pressure that drives current through the components.

💡Ammeter

An 'Ammeter' is used to measure the flow of electric current in a circuit. The script describes its symbol as a circle with an 'e' in it. This device is essential for understanding the amount of current flowing through a circuit, which is a core concept in the study of electricity.

💡Resistor

A 'Resistor' is a component that restricts the flow of electrical current. The video script describes its symbol as a rectangle, which is a simple yet effective way to represent its function within a circuit. Resistors are crucial for controlling the amount of current that passes through different parts of a circuit.

💡Variable Resistor

A 'Variable Resistor' is a type of resistor that allows the resistance to be adjusted. The script describes its symbol as a rectangle with an 'R' through it, symbolizing the ability to change the resistance. This component is vital for circuits where the current needs to be dynamically controlled.

💡Bulb

A 'Bulb' is a device designed to convert electrical energy into light energy. The video mentions two symbols for a bulb, one being a circle with a cross and the other a circle with an 'alms' in it, which is likely a playful misspelling of 'lamp'. Bulbs are a common component in circuits and serve as a practical example of energy conversion.

💡Motor

A 'Motor' is a device that converts electrical energy into kinetic energy. The script describes its symbol as a circle with an 'M' in the middle. Motors are essential in various applications where motion is required, and they represent another form of energy conversion in electrical circuits.

💡Diode

A 'Diode' is a component that allows current to flow in one direction only. The video script uses creative mnemonics to help remember the symbol, which resembles an arrow with a blocker. Diodes are crucial in electronic circuits for controlling the direction of current flow.

💡Thermistor

A 'Thermistor' is a resistor that changes its resistance with temperature changes, acting as a heat sensor. The script describes its symbol as resembling a thermometer going through a resistor. Thermistors are used in circuits where temperature sensing is required, linking the physical world with electrical signals.

💡LDR

An 'LDR', or Light Dependent Resistor, is a resistor that changes its resistance in response to light changes. The video script uses a story about lampposts and candles to illustrate how LDRs can be used in modern electronic systems. The symbol for an LDR is described as a rectangle in a protective bubble, symbolizing its use in light-sensitive applications.

💡LED

An 'LED', or Light Emitting Diode, is a type of diode that emits light when current flows in the forward direction. The script describes its symbol as a diode with arrows representing light emission. LEDs are widely used for illumination in various electronic devices and are an excellent example of energy conversion from electrical to light.

💡Fuse

A 'Fuse' is a safety device in a circuit that prevents excessive current flow by breaking the circuit if too much current is detected. The video script describes its symbol as similar to a halt sign, which is fitting given its role in stopping current flow when necessary. Fuses are crucial for protecting electrical circuits and devices from damage due to faults.

Highlights

Introduction to the names and symbols of electrical components used in circuits.

Explanation of a cell's function in providing electrical energy and creating current.

Description of cell polarity with positive and negative sides.

Memory aid for cell polarity using the concept of addition and subtraction.

Function of a battery as a collection of cells providing large amounts of electrical energy.

Illustration of a switch with a humorous Harry Potter glasses analogy.

Operation of a switch in allowing or stopping electrical current flow.

Introduction to voltmeters for measuring voltage with their symbol.

Explanation of ammeters for measuring current with their symbol.

Role of resistors in restricting the flow of electrical current and their symbol.

Introduction to variable resistors and how they can change electrical current.

Symbol for variable resistors and a creative way to remember it.

Function of bulbs in converting electrical energy into light energy with two possible symbols.

Explanation of motors converting electrical energy into kinetic energy.

Symbol for diodes and a creative mnemonic for remembering it.

Introduction to thermistors as heat sensors and their changing resistance with temperature.

Symbol for thermistors and a creative analogy to remember it.

Explanation of LDRs as light sensors and their resistance change with light.

Symbol for LDRs and a story to help remember it.

Introduction to LEDs as diodes that emit light in the forward direction.

Symbol for LEDs and their function.

Explanation of fuses and their role in preventing excessive current.

Symbol for fuses and their protective function in circuits.

Closing remarks with encouragement and a call to subscribe for more educational content.

Transcripts

[Applause]

hello its GCSE physics explained I'm

going to teach you the names and symbols

of electrical components used in

electrical circuits and a little bit of

information about what they do a Cell

provides electrical energy to push

electrons around a circuit and create

current north at the large side of the

cell is the positive side and the

smaller side of the cell is the negative

side I teach my students that if you add

something it gets bigger so the bigger

side has the plus sign and if you take

something away it gets smaller so the

smaller side has the minus sign the

battery is a collection of cells joined

together in series with the negative end

of one cell connected to the positive

end of the next it provides a large

amount of electrical energy to push

electrons around a circuit and produces

bigger currents

the switch these are Hari Potter's

glasses here a wizard Harry

warning image it's a closed switch and

it allows an electrical current to flow

these are Harry Potter's broken glasses

only gettin again it's an open switch

which stops electrical current from

flowing voltmeters measure voltage which

is sometimes called potential difference

it's just a circle with a V in it

[Music]

Aamir's measure current it's just a

circle with an e in it resistors

restrict the flow of electrical current

it's just a rectangle variable resistors

you can change the size of the

resistance so you can make the

electrical current bigger or smaller to

draw the symbol just draw a rectangle

like a fixed resistor but then put an R

all through it on an angle a bit like a

Leever you could pull with an

upside-down V on the end V for variable

bulbs all lumps are designed to convert

electrical energy into light energy

there's two symbols you might see this

one which is a circle with a cross in

the middle a bit like an x-men badge is

the future truly sent or this symbol

which is a circle with an alms ein in

the middle which is relevant because

bulbs have got a high resistance and

heat up so much that they glow and give

off light mortars convert electrical

energy into kinetic energy the symbol is

just a circle with an M in the middle a

diode allows current the only flaw in

the forward Direction one way of

thinking about how the symbol looks is

it's an arrow point in which we're the

current can flow with a blocker at the

front to stop the current flow in

backwards or as I see it my students

it's a D and an i and an O which is the

first three letters of diode and that

just goes to show that what can I first

seem like one of the hardest symbols to

remember with a bit of creative thinking

you can turn it into one of the easiest

symbols to remember and that's like

anything in life a good strategy makes

things easier to learn

thermister well it's a golf club through

a resistor isn't it

thermistors are used as heat sensors

they are resistors that change their

resistance as the temperature changes

I suppose the symbols look a bit like a

thermometer going through a resistor at

an angle an LDR an LDR is a light sensor

it's a resistor that changes its

resistance when the light changes let me

tell you a little story in the olden

days lampposts used to have candles in

them that someone would have to light

well these dears it's all electronic

using LD Oz the symbol for an LDR starts

off by drawing a normal resistor like a

rectangle but because it might be on the

top of a lamppost we'd better put it in

a protective bubble to make it

waterproof in case it reals now here's

the sun's rays shine and down on it

making its resistance change and now

remember in my story turns the symbol

for the LDR from one of the hardest

symbols to remember to one of the

easiest and that's because the Brean

is quirky in the way it likes to work

[Music]

LED stands for light emitting diode it's

just a diode that emits light when

current is flowing in the forward

direction and doesn't emit light when

current is trying to floor but what's

this symbol is the CM is a diode but

with our laws representing light coming

out of it

the fuse causes a brick in a circuit if

an electrical appliance becomes faulty

and causes too much current Leflore the

fuse is a thin wire inside a small glass

casing so the symbol is quite similar

looking a halt that's being useful for

you there will be lots more 3d

animations coming up in future videos

thank you very much work hard and be

nice want to see more videos like this

subscribe my channel GCSE physics

explained bye for now