Questions tagged [voltage]
Voltage is the unit of measurement for electronic potential, from one point location to another.
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High voltage power lines - clarification of energy loss
I've been having a bit of trouble understanding the high-voltage power lines. If I was sending power from $A \rightarrow B$, we have:
Ohm's law $V = IR$
Power lost in the form of heat $P = I^2 R$
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Why is the voltage drop across an ideal wire zero?
I'm having trouble conceptualizing why the voltage drop between two points of an ideal wire (i.e. no resistance) is $0~V$. Using Ohm's Law, the equation is such:
$$
V = IR \\
V = I(0~\Omega) \\
V = 0$...
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How electric currents can flow between 2 points at the same potential?
According to Ohm's law, if there is a potential difference, $V$, across a resistor then there is a current, $I$, flowing through it.
Since we assume that points along the connecting wire are at the ...
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What is the difference between electric potential, electrostatic potential, potential difference (PD), voltage and electromotive force (EMF)?
This is a confused part ever since I started learning electricity. What is the difference between electric potential, electrostatic potential, potential difference (PD), voltage and electromotive ...
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What causes an electric shock - Current or Voltage?
Though voltage and current are two interdependent physical quantity, I would like to know what gives more "shock" to a person - Voltage or Current? In simple words, will it cause more "electric - ...
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Why do we use Root Mean Square (RMS) values when talking about AC voltage
What makes it a good idea to use RMS rather than peak values of current and voltage when we talk about or compute with AC signals.
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I don't understand what we really mean by voltage drop
This post is my best effort to seek assistance on a topic which is quite vague to me, so that I am struggling to formulate my questions. I hope that someone will be able to figure out what it is I'm ...
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Why do birds sitting on electric wires not get shocked?
When we touch electric wires, we get shocked. Why don't birds sitting on electric wires not get shocked?
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Potential difference across a zero resistance wire
So I started off with electrostatics and everything seemed nice and mathematical and justified and then "DC circuits" happened!
I just cannot understand the model of electron flow in electrical ...
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How do electrons "know" to share their voltage between two resistors?
My physics teacher explained the difference between voltage and current using sandwiches. Each person gets a bag full of sandwiches when they pass through the battery. Current = the number of people ...
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Voltage drop along an idealized resistance-free wire in a circuit?
If you connected the positive terminal of a battery to the negative terminal to a battery with a wire with (hypothetically) no resistance, and are asked to give the voltage drop of a segment of wire ...
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Why high voltage transmission lines?
This is a question which I seem to have tackled multiple times, solved each time after reading a dodgy internet explanation, then partially forgotten about and retackled half a year later. It is time ...
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What determines the forward voltage drop for a diode?
I have always had the idea that the forward voltage drop in a semiconductor diode was related in a simple way to the bandgap energies in the semiconductor. However this is apparently not the case:
...
rob♦
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Why does vacuum have a nonzero characteristic impedance towards electromagnetic radiation?
On Wikipedia, the impedance of free space $Z_0$ is defined as square root of the ratio of the permeability of free space $\mu_0$ to the permittivity of free space $\epsilon_0$, i.e.
$$Z_0 = \sqrt{\...
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Are voltages discrete when we zoom in enough?
Voltages are often thought of as continuous physical quantities.
I was wondering whether by zooming in a lot, they are discrete.
I feel like the answer to the above question is yes as voltages in the ...
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