The Generation of Voltage in a Transformer

[TillEulenspiegel]

Ah I think I see your disconnect. The issue is one of permeability .
Air= Mu of 1 ,iron = mu of 1000.

When a coil , like a solenoid generates a mag field , there is a small mag field on the outside, while the shape and diameter of the hole ( usually <1/2') tends to focus the field towards the interior, wrapping an additional coil around the first mearly absorbs the existent mag field and even though the Mu of wire ( copper) is ~ to air it can actually couple and channel the emf to be used as an inductive current. The result however will be an inefficient transfer of the mag field, now if we add an iron core, the subsequent field is orders of magnitude higher and the field collapse transfers more emf to the additional coil.

This is a good site for understanding transformers,solenoids,generators, ect.
http://hyperphysics.phy-astr.gsu.edu/hbase/magnetic/transf.html#c1

 

[binaryblade]

Originally posted by david90
since dc won't work with a transformer, what if u charge a capacitor with dc circuit then discharge it to a transformer, would the voltage be amplified? why?

When u first connect a dc power to a transformer, doesn't the voltage gets amplified then drops to zero? change in magnetic field right?

also, I'm hearing people say that amp kills not voltage. So if u cut yourself and stick a 9v bat to the cut, it would kill u? Would a 1.5v bat kill if the resistance of ur body is low enough to get high amp?

The van graf machine makes 10k volt so why is safe to touch it? Would u feel a shock if ur barefooted and touched the dome?

it should be metioned that it is neither voltage nor amps that kill it's power (the combination there of) if you could crank low voltage at many amps or high voltage at low amps either will kill.

 

[Electrician999]

Transformer operation

I am a journeyman electrician and I had a helper ask a question I really didn't know how to respond to. If you apply 480V to the primary of a transformer and step down to 120/208, how exactly is the voltage "created." I understand the principal of induction but the way he was asking it was "In an electrical circuit you utilize the energy through a light bulb or motor, etc. How is it able to alternate when you're not using it?" The best way I could explain it is that the induction is using the field that the primary creates and the induction is mutual between the coils. I'm not sure if that was the best response... any ideas?