Re: Newbie - Current, Voltage, Resistance, Power and Transformer theory
- From: jasen <jasen@xxxxxxxxxxx>
- Date: 17 Oct 2006 07:34:32 GMT
On 2006-10-16, hdjim69 <hdjim69@xxxxxxxxxxx> wrote:
I'm self-teaching myself electronics and the only place to ask
questions is in this forum so please excuse me if this has been asked
a million time already but after reading several books, I still have
questions on these topics. No real values, just theory in this
question.
Rather then pushing a
huge amount of current we have a very high voltage say 200,000 to
600,000 volts and a low amount of amps (current). But how can we have
this HUGE amount of "pressure" (the typical explanation of what
voltage is) and hardly any current ?
It's like the difference between a fire hydrant (high flow low pressure)
and and a water blaster (high pressure low flow),
the 330kV distribution lines have isulators over 1m in length, they need to
be that size to resist the pressure of all that voltage.
I've been reading that voltage
and current are proportional - the more voltage the more current.
Correct, that is Ohm's law...
they are only proportional when the resistance remains the same.
Ahh... but this isn't the case really since current is a variable
value. It depends on the amount of resistance. So getting back to the
transmission lines, if we have HIGH voltage and LOW current then
resistance MUST be high.
when you're dealing with AC impedance is the term that's used and yes the
impedance is high. You can think of impedance being like resistance until
you encouter the part in the book that explains the difference.
The high impedance seen on is the high voltage side of the step-down transformer.
On the low voltage side the real load is located.
the transformer by tansforming the high voltage into low voltage is also
transforming the low impedance load into a high impedance one (when measured
from the high voltage side).
Bye.
Jasen
.
- References:
- Prev by Date: Re: ink circuit
- Next by Date: Finally: the end of the "Scooter Saga"
- Previous by thread: Re: Newbie - Current, Voltage, Resistance, Power and Transformer theory
- Next by thread: Re: How can a neutron have magnetism if it is has no electricity?
- Index(es):
Relevant Pages
|
