6.7 Electromagnetic Induction - Intro + Faradays Law Flashcards
What is electromagnetic induction?
The creation of emf and therefore of current by using motion of electrical conductors in a magnetic field.
Where is this technique used everyday?
At the creation of electrical energy at out homes.
How is emf induced when a wire cuts through a magnetic flux?
The charge carriers will experience a force , causing them to accumulate at one end. This creates emf along the ends.
When talking about current being induced what do we also need to mention?
That emf is induced. And due to this current is induced.
How can we increase the emf/current induced during electromagnetic induction? 4 ways
- increase coils on wire
- increase magnetic flux density
- larger cross sectional area of coil
- move magnet/coil of wire faster
What needs to happen to the magnetic flux for current/emf to be induced?
It needs to change when interacting with an electrical conductor. This can be by moving the wire or switching on/off the field.
How can we tell how strong the value of emf will be?
It is the rate of change of flux linkage/magnetic flux.
How is energy transferred when using eletromagnetic induction? - in terms of stores
The kinetic energy is transferred to the electrical potential store
What is faraday’s law?
the magnitude of emf is equal to the rate of change of flux linkage/magnetic flux?
Equation linked to faraday’s law? What does each symbol represent?
e = delta Φ / delta t e = emf Q = magnetic flux linkage or magnetic flux t = time
What does this equation give and doesn’t give? - magnitudes directions etc.
Gives only the magnitude of emf but not its direction
What would be gradient of a Q/t graph?
EMF
What is the conclusion if gradient of Q/t graph is flat (0)?
No emf is induced and therefore no current
What is the area of an emf time graph?
magnetic flux / magnetic flux linkage
