The voltage tag has no wiki summary.
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0answers
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How much current would be generated by polarity reversal of Earth's magnetic field?
Continuing from my previous question Is reversal of magnetic polarity in a planet an instantaneous occurence?
A change in magnetic flux is expected to generate an EMF.
In the case where the ...
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2answers
296 views
Calculate power $P=V \times I$
I have an adapter which mentions like this...
Input: 100-240V~1.8A
50-60hZ
So how much power does it really consume?
I just knew ...
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3answers
3k views
How is calculated the potential between two capacitors in series?
Suppose to have two capacitors in series:
The voltage in the middle point will be:
$$
V_X = V_1 \frac{C_1}{C_1+C_2}
$$
How can this be explained? It's been asked in electronics, and explained in ...
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1answer
171 views
Emf Of a Cell in a common circuit
My questions will be based on the above figure.
The Emf Source V1 and R1 Together form a cell(R1 is internal resistance)
R2 Represents the entire load on the source
VoltMeter
My teacher told ...
6
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2answers
338 views
Voltage and current of positive lightning
For a physics issues investigation I chose to investigate what effects lightning could have on an aeroplane while in flight if it was struck and then go on to discuss some possible implications of ...
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2answers
170 views
Fundamentality of voltage to current
From Ohm's Law :
Ohm's law states that the current through a conductor between two points is directly proportional to the potential difference across the two points.
I would like to know if ...
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3answers
539 views
Why does the potential drop across a battery and resistor equal the emf of the battery?
In this diagram you can see the potential difference across the battery and resistor is the same as the pd created by the battery (the battery and resistor are representing a battery with internal ...
2
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1answer
523 views
How does a voltage independent current source work?
So I'm having some trouble understanding what a voltage independent current source is. How can you have a current without a voltage. as I understand it voltage or EMF is the force that drives the ...
2
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2answers
552 views
is the voltage drop of a battery that is being short circuited the same as the battery's advertised voltige
So I know this is a pretty fundamental question, but I'll ask it any way. lets say you have a 12V battery, and the positive is connected to the negative directly by a wire with negligible ...
0
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1answer
308 views
Potential difference between conductors
Reading some books there is something that i don't understand. Is the capacitors topics when they name a potential difference between conductors.
As i know, Potential difference is the difference in ...
1
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1answer
67 views
is it possible to gain from charging cold battery
Is it possible to get higher load of energy into a battery if you charge it when its cold eg. +9C?
the battery is emptier, but does it let the power in?
Is it safe?
0
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2answers
308 views
How can you measure battery output to see if the wattage is accurate? [closed]
When you have a battery and it shows you the milliamperehours and volts. You can use those to calculate the wattage. How can you test the battery to see if its wattage is accurate or if the company ...
4
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1answer
121 views
Loopless voltage measurement
I think we are all very well familiarized with the classical voltmeter. Classical voltmeter has two conducting wires that bring two potentials into the box. In the box we have well controlled ...
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2answers
2k views
How do I calculate output voltage from a given supply voltage and resistance?
I have searched everywhere but I can't seem to find out how I can calculate the output voltage (or voltage over a component) from the resistance of a resistor (or other component) and the supply ...
3
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2answers
142 views
Thought experiment with entangled electrons
Suppose we start out by having two entangled electrons. We separate them by some distance and we put one electron inside a thin loop of wire connected to an extremely sensitive voltage measuring ...
4
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1answer
192 views
What is the mathematics behind artificially generated plasmas via electric fields?
The ionization degree of a plasma is given by the Saha equation, which depends on the temperature and the particle specific ionization energy. In thermal equilibrium, the relation between ionization ...
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0answers
50 views
How can I figure out how many kWh's are in a battery using the mAh's and voltage. [duplicate]
Possible Duplicate:
Relating milliampere-hours to watt-hours for batteries
How can I figure out how many kWh's are in a battery using the mAh's and voltage.
Some batteries only list mAh's ...
0
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1answer
80 views
How to calculate the potential of the ball? [closed]
Consider 2 metals ,the smaller sphere has a radius of a carry +Q charges,what is the potential at the surface of the smaller sphere?
3
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1answer
190 views
Lifetime of battery
If I directly connect two terminals of 3V battery (negative to positive) using copper wire, would it lose all its charge faster compared to another 3V battery that is used to lighten a 1.5V bulb?
2
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3answers
4k views
Using A.C or D.C to create an electromagnet
Does it matter if I use A.C or D.C as a source to create an electromagnet? Or Does it depend on the voltage of current?
For example:
I have a coil which has about 50 turns. If I use same amount of ...
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5answers
291 views
How do electrical devices suck electricity?
If the electric potential is 220V and some device needs 1500watts then how does it suck exactly that amount of electrical energy from outlet?
2
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5answers
435 views
Why doesn't an electron accelerate in a circuit?
Why don't electrons accelerate when a voltage is applied between two points in in a circuit? All the textbooks I've referred conveyed the meaning that when an electron traveled from negative potential ...
2
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1answer
147 views
What electric potential is found over individual resistors connected in series to an AC power supply?
Given a set of resistors connected in series to an AC power supply:
What formula governs the peak-to-peak voltage which will be measured when voltage is probed over individual resistors and sets of ...
2
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2answers
722 views
Voltage and Current in transformers
In transformers, the ratio of the voltages equals the ratio of the turns - so double the output coil's turns and the output voltage doubles. Then, in order to conserve energy, current halves.
This ...
2
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2answers
697 views
What is the potential difference between point X and point Y?
Here is the problem:
In the above figure I want help on finding the potential difference between X and Y.
It is getting quite confusing due to the battery in the middle. I found the current in both ...
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8answers
3k views
What is the difference between electric potential, voltage and electromotive force?
This is a confused part ever since I started learning electricity. What is the difference between voltage and electromotive force (emf)? Both of them have the same SI unit, right? I would appreciate ...
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1answer
1k views
When does voltage drop occur?
Why or when does it occur in a circuit? What does it imply when you speak of a voltage drop across a resistor? (Obviously, it probably means that the current's voltage before the resistor is higher ...
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6answers
6k views
Difference between current and voltage sources
I am confused about the current and voltage. My intuitive example would be that of a pipe of say water. The diameter of the pipe determines the amount of water flowing per second but the pressure is ...
