Magnetism - Paper 2 Flashcards
To revise magnetism (paper 2)
What will two north poles do to each other?
Repel
What will two south poles do to each other?
Repel
What will a south and north pole do to each other?
Attract
Is mangentism an example of a contact or non contact force?
Non contact
State some differences between permanent and induced magnets
- A permanent magnet always has a magnetic field.
- An induced magnet only becomes magnetic when placed in a magnetic field.
- Induced magnets always causes force of attraction.
- Permanent magnets can attract or repel
State the magnetic materials
- Iron
- steel
- cobalt
- nickel
What do we call the region around a magnet where a force acts on another magnetic material?
Magnetic field
Which direction do magnetic field lines point in?
North to South
What do magnetic fields line show?
- The closer the fields lines the stronger the field.
- The arrows show the direction of force a north pole would feel.
Describe the magnetic field pattern around a bar magnet
Field lines loop from the North pole to the south pole
What is the relationship between the size of attraction/repulsion and distance from a magnet
As distance increase the force or field gets weaker
Where is the strength of a magnetic field the strongest?
The poles of a magnet
Why do magnetic field lines always need arrows on them?
The direction of the magnetic field at any point is given by the direction of the force that would act on another north pole placed at that point.
Describe how a magnetic compass works
A magnetic compass contains a small bar magnet.
The Earth has a magnetic field. T
he compass needle points in the direction of the Earth’s magnetic field.
Describe how a magnetic compass can be used to find the pattern around a bar magnet.
- Put the magnet in the middle of the piece of paper and draw around it.
- Draw nine dots around the north end of the magnet.
- Put a plotting compass on the paper so that its tail is over one of the dots.
- Draw a dot on the paper near to the point of the compass.
- Join the two dots and mark the line with an arrow.
- Then move the compass so that its tail is over your new dot.
- Make another dot next to the point.
- Repeat until you come to the edge of the paper or loop back round to the south pole.
When a current flows what is always created?
A magnetic field
Describe the magnetic field pattern around a straight wire carrying a current.
In circualr loops around the wire.
Describe the right hand rule for a straight wire carrying a current
Thumb points in the direction of the current, fingers curl around in the direction of the magnetic field
What factors affect the strength of the magnetic field produced by a current?
- Size of the current
- Distance from the wire
What is a solenoid?
When a current carrying wire is turned into a coil. this will increase the strength of the magnetic field.
Describe the magnetic field inside a solenoid
The magnetic field inside a solenoid is strong and uniform. This is shown by parallel staight lines that are close to each other.
Describe the magnetic field around a solenoid
The magnetic field around a solenoid has a similar shape to that of a bar magnet. It loops from North to South