Strength of an electromagnet
I can accurately measure the strength of an electromagnet to analyse how different factors affect it.
Strength of an electromagnet
I can accurately measure the strength of an electromagnet to analyse how different factors affect it.
Lesson details
Key learning points
- A soft iron core increases the strength of an electromagnet because it becomes magnetised when it is turned on.
- The more tightly wound the coil of wire is in an electromagnet, the stronger its magnetic field.
- The greater the current through the coil of an electromagnet, the stronger its magnetic field.
- The strength of an electromagnet is directly proportional to the current through it.
Keywords
Coil of an electromagnet - An insulated wire wound into the shape of a spring.
Turn of wire - A single loop of wire in a coil.
Soft iron - Very pure iron that cannot be made into a permanent magnet.
Directly proportional to - Describes the relationship between two variables, in which doubling the value of one variable doubles the value of the other.
Error bars - These show the accuracy of each measurement on a graph.
Common misconception
Digital ammeters are always accurate to the smallest amount they display.
Show pupils a copy of the specifications of the ammeters they are using that show how accurate they really are.
Equipment
For each group, or for a demonstration: a digital balance, boiling tube, clamp and stand, lab pack, ammeter, connecting wires, single core insulated wire, two crocodile clips and a bar magnet.
Content guidance
- Risk assessment required - equipment
Supervision
Adult supervision required
Licence
This content is © Oak National Academy Limited (2024), licensed on Open Government Licence version 3.0 except where otherwise stated. See Oak's terms & conditions (Collection 2).
Lesson video
Loading...