Magnets and Electricity
Grade 4 · Science · Study Guide
Explore the amazing forces of magnetism and electricity that power our world.
Magnets are objects that produce an invisible force called a magnetic field. This field can attract (pull toward) or repel (push away) other magnetic materials. Every magnet has two poles: a north pole and a south pole. Opposite poles attract each other — north and south pull together. Like poles repel — north pushes north away. Iron, nickel, and cobalt are the most common magnetic materials.
Electricity is the flow of tiny particles called electrons through a material. Materials that let electrons flow through them easily are called conductors — most metals are conductors. Materials that block the flow of electrons are called insulators — rubber, plastic, and wood are insulators. A circuit is a complete path for electricity to flow. A simple circuit has a power source (battery), wires, and a device like a light bulb.
Magnetism and electricity are closely related. An electric current creates a magnetic field. A magnet moving near a wire creates an electric current. This connection is what makes electric motors and generators work. Electromagnets are magnets made by running electricity through a coil of wire — they can be turned on and off!
| Conductors | Insulators |
|---|---|
| Copper wire | Rubber |
| Aluminum foil | Plastic |
| Steel nail | Wood |
| Gold | Glass |
Key terms
- Magnet
- An object that produces a magnetic field and can attract magnetic materials
- Magnetic poles
- The two ends of a magnet (north and south) where the magnetic force is strongest
- Conductor
- A material that allows electricity to flow through it easily
- Insulator
- A material that does not allow electricity to flow through it
- Circuit
- A complete path for electricity to flow from a power source through a device and back
- Electromagnet
- A magnet created by running electricity through a coil of wire
Flashcards
- Magnetic poles
- North and south ends of a magnet — opposite poles attract, like poles repel
- Conductor
- Material electricity flows through easily (copper, aluminum)
- Insulator
- Material that blocks electricity (rubber, plastic, wood)
- Circuit
- Complete path for electricity to flow
- Electromagnet
- Magnet made by running electricity through a wire coil — can be switched on/off
- Magnetic field
- The invisible area of force around a magnet
Practice questions
What happens when two north poles of magnets face each other?
- They attract
- They repel
- Nothing happens
- They create electricity
Show answer
Answer: They repel
Like poles (north-north or south-south) repel each other. Only opposite poles (north-south) attract.
Which material is a good conductor of electricity?
- Rubber
- Wood
- Plastic
- Copper
Show answer
Answer: Copper
Copper is an excellent conductor of electricity, which is why most electrical wires are made of copper.
A circuit must be complete for electricity to flow.
Show answer
Answer: True
For electricity to flow, the circuit must be complete with no breaks. An open circuit (break in the path) stops current flow.
An electromagnet cannot be turned off.
Show answer
Answer: False
An electromagnet can be turned on and off by switching the electric current on or off — this makes them very useful.
A material that blocks the flow of electricity is called an ___.
Show answer
Answer: insulator
Insulators like rubber and plastic block electricity from flowing, which is why wires are coated with plastic for safety.
Fun facts
- Earth itself is a giant magnet — that's why compasses always point north!
- The world's strongest electromagnets can lift cars weighing thousands of pounds.
- Lightning is a giant electrical spark between clouds and the ground.
Get a personalized course on Magnets and Electricity built around your child.