Magnetism Flashcards
What happens when current flows through a wire?
A magnetic field is formed around the wire
What is the rule for current flowing through a wire?
RIGHT HAND RULE,
The thumb is the direction of current and the fingers wrapped around the thumb is the direction of the magnetic field.
The closer to the wire, the stronger the magnetic field.
What is the magnetic field around a wire made of?
Concentric circles
Does the magnetic field around a wire have poles?
No
How to increase the magnetic field around a wire?
Increasing the current flowing though the wire
What happens to the magnetic field when a wire is looped?
When a wire is looped into a coil, the magnetic field lines circle around each part of the coil into the centre of the coil
How to increase the magnetism around a wire?
Increasing the amount of coils to form a solenoid
Properties of a solenoid
The magnetic field inside the solenoid is strong and uniform
One end of the solenoid behaves like a south pole and the other end behaves like a north pole.
If the current changes direction, the north pole and south pole will switch
What does it mean if there is no magnetic field around a wire?
There is no current
How to increase the magnetic field around a solenoid?
Increasing the size of the current
Increasing the amount of coils
Adding an iron core
What will the iron become when wrapped inside a solenoid?
An induced magnet
What is an electromagnet?
A solenoid with an iron core
The magnetic field produced from the magnet can be turned on and off by turning the current on and off
Examples of electromagnets
A scrap yard crane.
An electric bell (explanation on flashcard)
What is the motor effect?
Occurs when a wire with current flowing through it is placed in a magnetic field such as in between two magnets
This makes the wire experience a force
Factors affecting the force in the motor effect
- Using stronger magnets
- Increasing the current
- Placing the wire 90 degrees to the direction of the magnetic field lines between the poles of the magnet (RESULTS IN MAXIMUM INTERACTION)