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Shorting collector to base is NOT redundant, it serves the useful purpose of making conduction in the two transistors similar. In particular, the construction of a transistor includes a thin base reg …

Yes, there is a definite RC time constant for any given resistor and capacitor. There are also other time constants for real components, related to stray inductance, skin effect, and sometimes mecha …

That's an ammeter, not a voltmeter, and "there's no voltage drop" just suggests the ideal-ammeter characteristic of zero resistance, as the correct approximation to apply. There can, of course, be cur …

You say 'no pressure (voltage) to push the electrons', but doesn't that mean there's no acceleration of the electrons? They're already in motion, and they stay in motion. Were the current to drop, th …

The cylinder IS a pole piece of the magnet, just as the concave shapes are. The induction of the winding is hoop-like, not radial at all. So, the cylinder makes the permanent magnet field nearly r …

Johnson noise, like Brownian motion, is an observable effect of temperature in a population of identical particles. What you measure, with an ideal voltmeter across a resistor, is the small fluctuatio …

Current in a circuit, like movement of links in a circulating bicycle chain, does not vary from one location (like the top of a waterfall) to another. The 'liquid flow' analogy is just.. an analogy, …

I think the intent of that statement is that the current in the secondary windings, if there's a good current-carrying load present on the secondary terminals, acts in the opposite sign to the primary …

Circuits are approximately devoid of node capacitance (i.e. unlike the sphere atop a van de Graaff generator, they are presumed to hold negligible net charge), so the voltmeter (in circuit-theory ap …

It is a normal practice (for measurement purposes) to balance a resistor pair against a capacitor pair (in a bridge measurement...). In that situation, the expected balance occurs when the capacitan …

The windings (wire) of a transformer have some electrical resistance; your secondary voltage will drop from the induced voltage (EMF) by the current times the secondary winding resistance as well as t …

A wire is used to conduct electricity along its length. So, in normal usage, with all current parallel to the axis of the cylindrical wire, the electric potential is a function only of the length di …

No, a short circuit needn't be an overload. There are circumstances (like in current transformers) where no load, however small in resistance, is an overload. There are ideal signal sources that a …

If you apply a sinusoid generator to an RC series circuit, at t=0 the sine(2pi * f * t) is indeed zero. But the voltage on the capacitor is NOT zero, rather the sum of I*R and the capacitor voltage i …

Resistance, by definition, is a voltage divided by a current. So, a series of resistors has a terminal voltage which is the sum of the voltage drops of the individual resistors, and (because the resis …