Explore how electric current produces magnetism and heat, and see how these effects are used in everyday devices.
When electric current flows through a wire, it creates a magnetic field around it. Wrapping the wire into a coil around an iron core creates a stronger electromagnet.
What happens to the magnetic field around a wire if current stops flowing?
The magnetic field disappears, since it only exists while current is flowing
Why is an electromagnet stronger than a single straight wire carrying current?
Coiling the wire concentrates the magnetic field, and adding an iron core strengthens it further
When electric current flows through a resistor (like a wire with resistance), some electrical energy converts into heat energy.
Why does the filament of an electric bulb glow when current passes through it?
The heating effect of current makes the filament extremely hot, causing it to glow and emit light
Name one household appliance that uses the heating effect of electric current.
An electric iron, heater, or toaster
1. What does current flowing through a wire create around it?
2. What is an electromagnet?
3. Name one device that uses the heating effect of current.
4. Why do electromagnets lose their magnetism when current stops?
5. What happens to electrical energy when current passes through a resistor?