Electromagnets and transformers

• Electromagnetism is due to the magnetic fields around electric currents.
• The fields can cause forces with other nearby magnets which can be used to make motors spin.
• Electromagnets are made by wrapping a coil of wire around an iron bar and passing an electric current through the coil.
• The iron core in an electromagnet increases its magnetic field strength.
• A simple electromagnet is made by coiling wire around an iron nail.
• Electromagnets are used in devices such as electric bells, and door locks that can be controlled remotely.