Magnetic Fields in Solenoids Flashcards
All 6 cards in this deck
What is a solenoid?
A long coil of wire that produces a magnetic field when a current flows in it (an example of an electromagnet).
Why is the magnetic field inside a solenoid strong and almost uniform?
The fields from the individual coils add together along the centre of the solenoid.
Why is the magnetic field outside a solenoid weaker than inside?
The fields from the individual coils largely cancel each other outside the solenoid.
What does the magnetic field pattern outside a solenoid look like?
The same as the field of a bar magnet, with a north pole at one end and a south pole at the other.
Name three ways to increase the strength of an electromagnet.
Increase the current, increase the number of turns on the coil, add an iron core.
What are the steps to investigate how current affects the strength of an electromagnet?
e.g. testing currents of 1 A, 2 A and 3 A
- Change the current with a variable resistor and measure it with an ammeter: 1 A, 2 A, 3 A.
- Measure the strength each time, e.g. count the paper clips picked up.
- Keep the number of turns, the core and the coil the same (control variables).