physics - electro magnetism Flashcards
What are the names of the two poles of a magnet?
North (seeking) and south (seeking)
What is the direction of the force between two opposite magnetic poles?
Attracting
What is the direction of the force between two alike magnetic poles?
Repelling
What are the four main magnetic materials?
Iron, steel, cobalt and nickel
What is a magnetic field?
The region around a magnet where another magnet or magnetic material experiences a force
Where on a magnet is the magnetic field the strongest?
At the poles
What is a permanent magnet?
A magnet that produces its own magnetic field
What is an induced magnet?
A material that becomes magnetic when placed in a magnetic field
In what direction do magnetic field lines point?
From a north seeking pole to a south seeking pole of a magnet
What is the shape of the magnetic field around a current carrying wire?
Concentric circles centred on the wire
How is the strength of the magnetic field around a current carrying wire affected by the size of the current in the wire?
The larger the current the stronger the field
What is a solenoid?
A coil of wire
What is the name for a solenoid around an iron core?
Electromagnet
What effect does adding an iron core to a solenoid have on the magnetic field?
Makes it stronger
How is the strength of the magnetic field around a solenoid affected by the number of coils?
The larger the number of coils the stronger the field
What is the name for the effect where a current carrying wire in a magnetic field experiences a force?
The motor effect
When a current carrying wire is placed in a magnetic field, in what direction does the force act on the wire?
At right angles to both the field and the direction of current
What are the three factors that affect the size of the force on a current carrying wire in a magnetic field?
Strength of the field, the size of the current and the length of the wire in the field
What happens to a current carrying coil of wire in a magnetic field?
It starts to rotate
