1. Electromagnets

2. Electromagnets and Uses
WALT: Design an experiment and state the uses of electromagnets
I can design an experiment from scratch to test the strength of an electromagnet
I can explain several uses for electromagnets in real life

3. Remember how we made an electromagnet...
Could somebody come and draw the circuit diagram for us…?
Wrap the wire around the iron nail.
Connect a crocodile clip to each end of the wire
Plug the other end of the wires into the Power pack.
Turn the Power Pack on.

4. By the way, drawing that diagram is a classic CE exam question!

5. Mr T. is still thinking about buying an electromagnet for his scrapyard in Kangemi.
However, this time he wants you to test two other things that will affect the ability of his magnet to pick up cars:
The type of coil
The strength of current
These are the questions I want answered, fools;
Should I use an iron or steel core?
Should I use a 2 volt 4 volt or 6 volt current?

6. You will need to plan 2 little experiments to find out each of these two things
Spend 2 minutes planning in pairs. Answer these questions for each of the two experiments.
What will you change? (i.e what is the input variable?)
What will you measure (i.e. what is the outcome variable?)
What will you keep the same?
What will your tables look like (you’ll need a table for each experiment)

7. When finished
Write a short note to Mr. T, advising him of which 3 things (think back to last lesson) will increase the strength of his electromagnet
Use page 317 to write notes (not copy) on 3 ways an electromagnet is useful in real life (including its use as a RELAY)
Answer Q 1 and 2 on page 318