P7 - Magnetism Flashcards
What’s a magnetic field
Region where other magnets experience a non contact force
Where do the lines go on a normal north south magnetic
Lines go from north to south (on circular)- shows which way a force would act on the North Pole
At north end lines go outward. At south end lines go inward
What is attraction or repulsion
Two poles on a magnet near each other exert a type of force on each other
What do compasses show
Show the direction of magnetic fields
How do compasses work
They have a tiny bar magnet and the North Pole of this magnet is attracted to the south of any near magnet. When it’s not near a magnet, compass always points north due to earths magnetic field
What’s a permanent magnet
Magnet that produces its own magnetic field
What’s an induced magnet
Item of magnetic material that turns into a magnet when put I to a magnetic field.
What is the force between a permanent and induced magnet
Always attractive
What happens when a current flows through a wire
Magnetic field created around the wire - field of concentric circles perpendicular to the wire
What’s the right hang thumb rule
Point thumb in direction of current and curl fingers. The way fingers curl is the magnetic field
What does the strength of a magnetic field created from a current depend on
Larger current = stronger field
Closer to wire = stronger field
What’s a solenoid
A coil of wire
How can you increase the strength of a magnetic field of s wire
Wrapping the wire into a solenoid
How does a solenoid create a stronger magnetic field
Field lines around each other line lip up with each other. This results in lots of field lines pointing in the same direction that are very close to each other.
What’s the magnetic field like inside and outside a solenoid
Inside - uniform and strong
Outside - same it is round a bar magnet > means solenoid ends act as north and south poles
How to increase the field strength of a solenoid
Add iron bar Inside as it becomes an induced magnet from current
Or add more coils
What’s a solenoid with an iron core called
Electromagnet. A magnet in which it’s magnetic field can be turned on and off with a current
A current in a magnetic field experiences a …..
Force
What happens when a current carrying wire is out between magnetic poles
The magnetic field around the wire interacts with the magnetic field it’s been placed in. The magnet and conductor exert a force on each other which causes the wire to move
How does the magnetic field experience the full force
The wire has to be at 90 degrees
If the wire is parallel to magnetic force, no force. Angles in between = some force
What direction does force always act at to magnetic field
Force always acts at right angles to magnetic field of magnets and the direction of current int the fire
The strength of force increases with ….
The strength of the magnetic field and the amount of. Urgent
What’s the left hand rule
Left hand - First finger in direction of magnetic Force
SeCond finger in Current direction
thuMb pointing in direction of force (Motion)
