Superposition
Tam/WB2TT wrote:
You can come up with a lot simpler example that at first might look like a
paradox. Consider two DC current sources of 1 amp each. Each current source
will deliver 50 W to a 50 Ohm resistor. Now connect the two current sources
in parallel, and the resultant 2 amps will deliver 200W to the same 50 Ohm
resistor. There is nothing wrong here.
I see Cecil is still superposing his waves of average power.
I have an example that's more fun yet.
Take a 10 volt source and connect it through a 10 ohm resistor to
another 10 volt source. The positive terminals of the sources are
connected to the ends of the resistor, and the negative terminals are
connected together -- "grounded", if you prefer. Turn on one source,
leaving the other off. (An "off" voltage source is a short circuit.)
Result: 10 watts of dissipation in the resistor. Turn off the first
source and turn on the second. Result: 10 watts of dissipation in the
resistor. Now turn both sources on. Result: An exercise for the reader.
This is a linear circuit for which superposition holds.
Roy Lewallen, W7EL
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