P-7 Electromagnetism and Magnetism Flashcards
1
Q
What are poles of a magnet
A
- Places where the magnetic forces are the strongest
- Two like poles repel each other-
- Two alike poles attract each other
- Non- contact force
2
Q
What happens when two magnetics are brought close to each other
A
- They exert a force on each other
3
Q
What does a permanent magnetic produce -
A
- A permanent magnet produces its own magnetic field
4
Q
What is a magnetic field
A
- A region around a magnet where a force acts on another magnet or non magnetic material
- When removed from this field an induced magnet loses all its magnetism
- Depends on distance- strength
5
Q
What are permanent and induced magnets
A
- Permanent magnets produce their own magnetic field
- Induced magnets are magnetic materials that turn into magnets when put into magnetic field
- Force between permanent and induced is always positive
6
Q
How of compasses show the direction of magnetic fields
A
- Tiny bar magnet.
- North pole is attracted to south pole of any other magnet
- Compass points in direction of magnetic field its in
- -When not in field they point north-core metal
7
Q
- What is the direction of the magnetic field
A
- given by direction of force that would act on another north pole placed at point
- Magnetic field line is from the north pole to the south pole of a magnetic
8
Q
What happens when a current flows through a conducting wire
A
- A magnetic field is produced around the wire
- Strength depends in the current and distance
9
Q
- What happens when a wire is shaped to form a solenoid
A
- Increase in strength in magnetic field by a current through a wire
- Strong and uniform
- Similar magnetic field to bar magnet
10
Q
What is a solenoid
A
- Coil of wire where increased strength of magnetism can be seen
11
Q
why does a solenoid’s structure produce a stronger field
A
- This is as field lines around each loop line up
- Lots of field lines in same direction- very close- stronger
12
Q
What happens when you add an iron core to a solenoid
A
- Increases the strength
- Becomes induced magnet when current is flowing
13
Q
What is an electromagnet
A
- A solenoid with an iron core
14
Q
What is the motor effect
A
- When a conductor carrying a current is placed in a magnetic field the magnet producing a field and conductor exert a force on one other
- Conductor placed between magnets
15
Q
- How does the full force be experienced in the motor effect
A
- Wire has to be at 90oc to magnetic field
- if parallel it will experience no force
- Increases with amount of current that passes through
- Increases with strength of current passing through
