Transformers And Dynamos Flashcards
1
Q
What are eddy currents?
A
Small currents induces by changing magnetic flux in the iron core
2
Q
How is the effect of eddy currents reduced?
A
Laminating core with layers of insulation
3
Q
Why are transformers not 100 percent efficient?
A
Heat produced from eddy currents
Heat generated by resistance in the coils
4
Q
What is permeance of an object?
A
Amount of flux induced for a given no of turns of that type of coil
5
Q
What can we think of coil, permeance, current turns and flux as…
A
In order: power supply, Conductivity, emf, current
6
Q
Higher the permeance the ______ the flux induced
A
Greater
7
Q
What gives a high permeance?
A
High permeability, short and fat(large area) core
8
Q
What is a high permeability material?
A
Iron
9
Q
Air has a _________ permeability
A
Very low
