Electromagnet Strength
Electromagnet Strength is a free interactive simulation of how current, coil turns, and core material affect an electromagnet for GCSE Physics (Edexcel IGCSE 4PH1). Students vary the current, number of turns, and core material, and measure the number of paperclips the electromagnet can hold, to investigate what makes an electromagnet stronger. This is a required practical for Edexcel IGCSE 4PH1. No login required.
Aim: To investigate how current, coil turns and core material affect the strength of an electromagnet.
The steel core has kept some of its magnetism — it has become a weak permanent magnet. An iron core loses its magnetism as soon as the current stops.
Results
| # | Core | Turns | Current (A) | Paperclips |
|---|
- Choose the iron core, set the current to 1.0 A with 10 turns, and switch on. Record the number of paperclips.
- Keeping the turns and core the same, increase the current in 0.5 A steps, recording the paperclip count each time.
- Now keep the current fixed and change the number of turns. Record at least 5 readings.
- Finally, compare the air, iron and steel cores with the same current and turns.
- Plot a graph of paperclips against current using the Graph Builder. What pattern do you see? What happens when you double the current?
- Switch off while using the steel core, then while using the iron core. What is different, and why does this make iron a better choice for an electromagnet?