GCSE PHYSICS - MAGNETISM AND ELECTROMAG - LESSON 11 - electromagnets

Electromagnets: Understanding Their Functionality

Introduction to Electromagnets

• The lesson continues the exploration of electromagnets, building on previous knowledge about creating them by winding conducting wire into a solenoid or coil.

• A solenoid generates a magnetic field similar to that of a bar magnet, with distinct North and South poles determined by the direction of current flow.

Magnetic Field Strength

• The strength of the magnetic field produced by the solenoid is influenced by:

• The size of the electric current flowing through it.

• The number of turns in the coil; more tightly wound coils produce stronger fields.

Enhancing Electromagnet Strength

• To significantly enhance the magnetic field strength, a magnetic material must be inserted into the core of the solenoid.

• Inserting a soft iron core transforms the solenoid into an effective electromagnet, allowing for control over its magnetism.

Practical Applications and Characteristics

• When activated (switch closed), the electromagnet can pick up ferromagnetic materials like iron or nickel. Once deactivated (switch opened), it loses its magnetism immediately.