Magnetic fields and electromagnets Flashcards
What are magnetic forces caused by?
Invisible magnetic fields.
What is a magnetic field ?
The area around a magnet where another magnet or magnetic material (iron, nickel, cobalt and steel) feels a force.
Where is the magnetic field strongest at?
The poles
The strength of any magnetic field depends on what?
- the size of the current
- the distance from the wire
What is a solenoid?
A loop of wire coiled into a cylindrical shape
What do the field lines inside the coil of wire in a solenoid look like?
Evenly spaced, parallel, straight lines, strong
What do the field lines look like outside of the solenoid?
The field lines look like the field lines around a bar magnet, with a clear north and south pole.
The closer together the magnetic field lines…
…the stronger the magnetic field.
How is an electromagnet formed?
When a current carrying wire is wrapped around an iron core. The iron core increases the magnetic field strength of the solenoid.
What happens because of the motor effect?
When a wire with a current flowing through it is placed in a magnetic field, the magnet and the conductor will experience a force. This is because if the motor effect.
What causes the motor effect?
The field created by the electric current interacts with the magnetic field that the wire is placed inside. This causes the force on the wire.
