Electricity and magnetism are powerful forces that are all around us. From the lightning in storms to the compass in your hand, these forces shape our world and power our modern lives!
Have a question about electricity or magnetism? Type it below and get an answer!
Electricity is a form of energy resulting from the movement of charged particles like electrons. It powers our homes, schools, and many devices we use every day.
Current electricity is the flow of electric charge through a conductor. It's what powers our electrical devices and appliances.
Static electricity is an imbalance of electric charges on the surface of materials. It causes the familiar shock when you touch a doorknob after walking on carpet.
Portable chemical energy source
Energy from flowing water
Energy from the sun
Energy from moving air
Materials that allow electricity to flow through them easily.
Materials that don't allow electricity to pass through them easily.
Static electricity occurs when there's an imbalance of electric charges within or on the surface of a material. Let's explore this fascinating phenomenon!
When you rub a balloon on your hair, electrons move from your hair to the balloon. This creates opposite charges that attract each other.
A charged comb can bend a thin stream of water because water molecules are polar and get attracted to the charged comb.
Walking across carpet and touching a doorknob can give you a small shock due to static discharge.
Lightning is a giant static discharge between clouds and the ground or between different clouds.
Plastic wrap often sticks to itself and other objects due to static electricity generated when pulling it from the roll.
Use static electricity to attract toner particles to paper
Electrostatic air filters use static charge to trap dust particles
An electric circuit is a path that electricity flows through. It starts at a power source, flows through wires and components, and returns to the source. Let's learn about circuits!
Click on a component to learn about it!
For a circuit to work, it must be complete - electricity needs an unbroken path to flow from and back to the source.
Electricity flows in a continuous path
Electricity can't flow due to a break in the path
Components connected in a single path
Components connected in multiple paths
A short circuit occurs when electricity takes an unintended path of low resistance, bypassing the components. This can cause overheating, fire, or damage to devices.
Enables us to see in the dark
Powers phones, internet, TV
Powers medical equipment
Powers machines and tools
Refrigerators and freezers keep food fresh longer, reducing waste
Electric pumps help bring clean water to homes and communities
Powers computers and internet for learning and research
Electric lights make streets and homes safer at night
Electricity is very useful, but it can also be dangerous if not handled properly. Let's learn about electrical safety and how to prevent accidents.
Occurs when electricity passes through the body. Can cause pain, burns, muscle spasms, or even death.
Can be caused by short circuits, overloaded circuits, or damaged wiring. Electrical fires spread quickly.
Sudden increases in voltage that can damage or destroy electrical devices and appliances.
Always use dry hands when handling electrical devices or switches
Unplug appliances when not in use or during storms
Use proper plugs and sockets for the right appliances
Keep electrical devices away from water
Never touch exposed wires or damaged electrical cords
Don't overload sockets with too many plugs
Never use electrical appliances near water (like hairdryers near bathtubs)
Don't pull on cords to unplug devices; grab the plug itself
What would you do in these situations?
Magnets are objects that create an invisible force field called a magnetic field. This field can attract certain materials and either attract or repel other magnets.
Drag the magnets to see how they interact. Notice how like poles repel and unlike poles attract each other!
Lodestone (Magnetite): A naturally occurring magnetic rock. It was the first magnet discovered by humans thousands of years ago.
Artificial Magnets: Made from materials like iron, nickel, cobalt, and their alloys. They keep their magnetism for a long time.
Examples: Bar magnets, horseshoe magnets, refrigerator magnets
Induced Magnets: Materials that become magnetic when placed in a magnetic field, but lose their magnetism when removed from the field.
Examples: Paper clips, iron nails when near a magnet
Repeatedly stroke an iron or steel object with a magnet in the same direction. This aligns the domains in the material.
Passing an electric current through a coil wrapped around an iron core creates a temporary magnet (electromagnet).
When a magnetic material is placed near a magnet, it becomes a temporary magnet through magnetic induction.
Electromagnets are magnets created by electric current. They can be turned on and off and their strength can be adjusted, making them very useful for many applications.
OFF
Click the switch to turn the electromagnet on and off. Notice how it attracts metal objects when turned on.
Electromagnets can be made stronger by:
Uses electromagnet to move a clapper that hits the bell
Lifts heavy metal objects with switchable magnets
Uses electromagnets for levitation and propulsion
Convert electrical signals to sound using electromagnets
Can be turned on and off as needed
Power can be increased or decreased
Poles can be reversed by changing current direction
Can be made very powerful with enough current
Electricity and magnetism are closely related. Moving a magnet near a wire creates an electric current - this is how most of our electricity is generated!
This process is called electromagnetic induction, discovered by Michael Faraday in 1831. It's the basic principle behind most electricity generation today.
Modern power plants use the same basic principle as a simple dynamo, but on a much larger scale. Different energy sources are used to spin huge turbines:
Hard drives store data magnetically. Electric currents power processors that perform calculations.
Electric motors use electromagnets to convert electrical energy to mechanical energy for movement.
MRI machines use powerful electromagnets to create detailed images of the inside of the body.
Scientists and engineers continue to develop new technologies based on electricity and magnetism:
Using electromagnetic fields to transmit power without wires
Using quantum electromagnetics for advanced computing
Using powerful electromagnets to contain plasma for fusion reactions
Detecting tiny electrical signals from the brain to control devices
This simple generator demonstrates electromagnetic induction - the same principle used in power plants that generate electricity for our homes and schools!
Let's see how much you've learned about electricity and magnetism! Try this quiz to test your knowledge.
Want to learn more about electricity and magnetism? Try one of these fun projects:
Build a basic circuit with a battery, wires, switch, and bulb to learn how circuits work.
Create your own electromagnet using a nail, wire, and battery. See how many paper clips it can lift!
Build a simple electric motor using a battery, wire, magnets, and a few other materials.