Chapter 7 - Magnetism And Electromagnetism Flashcards
Which direction do magnetic field lines go in
The lines always go from north to south and they show which way a force would act on the North Pole if it was put at that point in the field
Where is the magnetic field strongest on a magnet
The magnetic field is strongest at the poles of the magnet. This means that the magnetic forces are also strongest at the poles
Why does the magnet always point north
This is because the Earth generates its own magnetic field, which shows the inside of the Earth (core) must be magnetic
What are the two types of magnets
Permanent magnets and induced magnets
What are permanent magnets
Permanent magnets produce their own magnetic field
What are induced magnets
Induced magnets of magnetic materials that turn into a magnet when they put into a magnetic field. When you take the magnetic field away from induced magnets, they quickly lose the magnetism and stop producing a magnetic field
What happens when a current flows through a wire
A magnetic field is created around the wire
What is the magnetic field that is created around the wire made up of
The field is made up of concentric circles perpendicular to the wire, with the wire in the centre. You can see this by placing a compass near a wire that is carrying a current. As you move the compass, It will trace the direction of the magnetic field
How can you increase the strength of the magnetic field of the wire
By wrapping the wire into a coil called a solenoid
How do you find the direction of the force with the left-hand flemming rule
Use your left hand
Your first finger points in the direction of the magnetic field
Your second finger points in the direction of the current
Your thumb with then point in the direction of the force (motion)
Flemings left-hand rule shows that if either the current or the magnetic field is reversed in the direction of the force also be reversed