All Questions
35
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Understand power rating in layman terms
I have recently started the chapter of electricity of class 8. I am not understanding the concept of power rating of appliances. When we say that a bulb is rated 220V-100W, which means, according to ...
0
votes
0
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40
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What is the difference between: “Electric Potential”, “Electric Potential Energy”, “Electric Potential Difference”, and lastly, “Voltage”? [duplicate]
Please provide very simple and specific examples/explanations when answering. Some have described Electric Potential as “work done per unit of charge”, but what exactly does “per unit of charge” mean? ...
- 11
0
votes
3
answers
223
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Why doesn't voltage increase when the wire length increases; there's more work to be done?
This Q&A did not answer my question.
The voltage of a circuit is the difference in each Coulombs potential energy at the negative pole, compared to the positive pole. At the negative pole, there's ...
- 248
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1
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39
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Given $\rm V=J/C$, is it better to think of the Coulombs as moving charge, or moving electrons?
I have been confused by how voltage is measured in joules per coulomb, until I thought of it in the context that the coulombs aren't measuring charge, but instead are measuring how many electrons are ...
- 161
3
votes
1
answer
1k
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What's the highest theoretical energy density in a chemical battery?
Is there a theoretical limit to how energy dense chemical batteries can be? How can one calculate them? And what stops us from reaching those limits?
- 55
-1
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1
answer
43
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Is it reasonable to think charge as an energy carrier? Why?
I learned in physics that potential difference is the work done on unit positive charge going from the point of lower potential to the point of higher potential. And electromotive force is the energy ...
- 421
4
votes
1
answer
433
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Can a 9 V battery kill you?
Suppose I connect a 9 V DC battery to a DC-to-AC converter. Then connect the output of the converter to a step-up transformer, which increases the voltage to 2000 V. Now, if I put myself between the ...
- 337
0
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1
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258
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What is the relation between electromotive force and energy stored in a cell which can be converted to other energy in the external circuit?
We usually define electromotive force of a cell as the energy stored in the cell(atleast I have noticed it to be defined like that). But isn't electromotive force equivalent to electric potential ...
- 598
1
vote
2
answers
352
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Stored energy of a capacitor
Imagine the two terminal of a parallel-plate capacitor are connected to the two terminal of a battery with electric potential difference $V$. If the capacitance of the capacitor is $C$, and the area ...
user310884
0
votes
1
answer
76
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Can voltage be considered simply a conversion factor?
Please correct my logic or lack thereof. It seems to me voltage or potential difference is only a conversion factor between charge and energy. Here's an example: Suppose 10 elementary charges are ...
-1
votes
1
answer
92
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Why is one joule equal to $V•C$? [closed]
I was asked a question how much work is done on a 5C particle with the potential difference of 6V.
I knew the answer is 30J
But the solution says :-
1V=1J/1C
therefore
W=30J/1C•1C
How can we derive ...
- 257
0
votes
0
answers
88
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Why does the voltage of a solar panel change as the tilt angle changes?
I performed an experiment where I linked a solar panel to a constant resistance, and took readings of the voltage and current every 10 minutes between 11:00 and 18:00. I performed this for 0, π/6, ...
- 75
-1
votes
1
answer
96
views
If you extracted 5 volts of energy from the human body for eight hours, how many calories would that burn? [closed]
I'm designing a device that is able to extract up to 5 volts from your body. I was wondering how many calories this would burn in eight hours? Suppose you went to sleep at night with this device ...
- 183
0
votes
3
answers
1k
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If voltage causes current to flow how can a battery have constant voltage but supply different amounts of current?
The question arises from the fact the voltage provided across battery terminals is constant no matter how much current is drawn (for non-ideal batteries the current draw is limited but still can be ...
1
vote
1
answer
213
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Why aren't salt water batteries used to power cars instead of lithium-ion?
I know salt water batteries are less efficient than lithium-ion, but water is safer, can be found anywhere, is cheap and 100% ecological. Even if it doesn't last long, you can refill anywhere. Why can'...
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