Hey there! Let's explore how moving electrical charges can create magnetic forces, and how magnets can make electricity flow!
Electricity and magnetism are closely linked. When electric current flows through a wire, it creates an invisible magnetic field around that wire.
We can build an electromagnet by wrapping a wire around an iron nail. When we turn the electricity on, the nail turns into a strong magnet!
The opposite is also true. Moving a magnet near a loop of wire pushes the electrons and generates an electric current. This is called induction.
✏️ Worked example
An engineer wants to make a simple electric generator to light up a small bulb. What two main parts does she need, and how should she use them to make electricity flow?
Identify the goal: We need to generate an electric current using the principles of electromagnetism.
Select the materials: We need a permanent magnet to provide a magnetic field, and a coil of wire to conduct the electricity.
Set up the system: Connect the ends of the wire coil to the light bulb to create a closed loop circuit.
Create motion: Spin the magnet rapidly inside or near the coil of wire.
Observe the result: The changing magnetic field pushes the electrons in the wire, producing an electric current that lights up the bulb.
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