Questions tagged [short-circuits]

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Will I get a shock holding a superconductive wire?

Assume a current carrying superconductive wire is in front of me, with no voltage source attached. If I hold it, will I get a shock? Forget for a minute that the superconducting wire will be too cold ...
• 3,697
1 vote
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A simple question about parallel connecting a short circuit (+the physical interpretation)

1. Introduction We know that $$1/R_1 + 1/R_2 = 1/R_t \ (equation \ 1)$$ $$\therefore R_t = \frac{R_1\times R_2}{R_1+R_2} \ (equation \ 2)$$ when $R_1$ and $R_2$ are connected in parallel and $R_t$ is ...
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What does it mean to ground in this context?

This is a homework problem that I already submitted, but am still unsure about. I am consider the following situation, re we have a conducting sphere of radius $R$ with charge $q$, which is surrounded ...
• 163
69 views

Is the eigenvalue of an eigenstate the same as its (global) phase?

I'm trying to understand Shor's Algorithm by reading this Qiskit textbook. At some part the following equation comes up: U |u_0\rangle = \frac{1}{\sqrt{12}} \begin{pmatrix} |3\rangle +...
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173 views

Why can you shortcircuit a car battery with a wrench in your hand and stay safe?

In this demonstration by Prof. Walter Lewin a car battery is shortcircuited with a wrench. The experimenter is holding the wrench in its bare hands, so why he is not experiences an electric shock? ...
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Kirchhoff’s Voltage Law validity in short circuited circuit

Imagine a circuit with a battery and a resistor. Now I connect a resistance-less wire in parallel with the resistor. There will be a potential difference between the two ends of resistor, so current ...
• 341
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A problem with the path of least resistance

I have a question about short circuits that I haven't been able to solve. From this we know: The total voltage V is constant, and the total current I is inversely proportional to the total resistance ...
260 views

Can grounding wrist prevent electrical shock?

Today while repairing some electronics and wearing anti-static wristband like on picture below I got thinking - in theory, would it be possible to avoid shock while working on mains by grounding ...
• 117
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Magnetic rail problem with inductor and battery (resistance less)

A metallic rod (negligible resistance) can slide frictionlessly on two parallel metallic rails separated by a distance l in the presence of a perpendicular magnetic field (B). The ends of the rails ...
• 43
1 vote
80 views

Earthing vs grounding

In some websites they say there is a difference between Earthing and grounding but some of them say they don't.Is there any difference between "Earthing" and "grounding"?
1 vote
47 views

Voltage - Current Relationship (IV graphs)

This is probably a really simple question but for some reason, I'm finding it difficult to grasp at an atomic level. My physics textbook has a statement that says: "As the voltage across a ...
1 vote
105 views

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Why doesn't Kirchhoff's Law work when a battery is shorted with an ideal wire?

Kirchhoff's law states that the sum of voltages around any closed loop sum to zero. The law is true as the electric field is conservative in circuits. Why can we not apply the law here? Why doesn't ...
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71 views

What's the source of voltage? [duplicate]

I've been told that in a DC circuit with a battery the negative terminal of the battery "pushes" electrons in nearby atom away of it and those by themselves cause electrons in other atoms to move, but ...
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Is there a non-zero field within an ideal current carrying wire?

Its true that there is a non zero field (in fact,a field of the magnitude of counter electric field inside the battery used) within a current carrying IDEAL wire (unlike static condition). Thus there ...
160 views

1 vote
1k views

The importance and the role of a switch in an electrical circuit

There is this simple test: Three identical bulbs are connected in the circuit illustrated in the figure. When switch $S$ is closed: a] The brightness of $A$ and $B$ remains the same, while $C$ goes ...
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