Electromagnetism Flashcards
When is a magnetic field created around a wire?
when a current flows through it
How can you visualise the magnetic field around a wire carrying a current?
by placing a compass near the wire, and as you move the compass, it will trace the direction of the magnetic field.
What happens if you change the direction of the current?
The direction of the magnetic field will change
What is the Right-Hand Thumb Rule used for?
-The Right-Hand Thumb Rule is used to determine the direction of the magnetic field around a current-carrying wire. -Point your thumb in the direction of the current and curl your fingers to show the direction of the field.
How does wrapping a wire into a coil (solenoid) or decreasing the length of a solenoid but keeping the amount of coils the same increase the strength of the magnetic field it produces?
Wrapping a wire into a coil (solenoid) increases the strength of the magnetic field because the field lines around each loop of wire align with each other. meaning they’d be closer together and more dense resulting in a stronger and more concentrated field.
What happens to the magnetic field lines around each loop of wire in a solenoid?
The magnetic field lines around each loop of wire in a solenoid align with each other, resulting in lots of field lines pointing in the same direction that are very close to each other
What is the role of an iron core in increasing the field strength of a solenoid?
-An iron core placed in the center of the solenoid further increases the field strength by becoming an induced magnet whenever current flows through the solenoid.
- a solenoid with an iron core is called an electromagnet
What are the 4 ways of increasing the strength of an electromagnet?
-by increasing the number of coils but keeping the length the same (can be done by wrapping a wire around)
-by decreasing the length but keeping the amount of coils (wraps) the same
-by increasing the current through a wire
- by putting an iron core through
