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Explain how positive and negative voltages can exist at the same time in a circuit but with only one voltage source?
Wiki User
∙ 12y ago
Voltages are relative. You could, for example, build a simple resistor voltage divider with two resistors and choose the middle point as ground. You would have minus and plus voltages relative to that point then.
It is also possible to generate minus voltage (relative to voltage source) with more complex circuitry from a single source. The circuit is called a charge pump.
AnswerPositive voltage exists between the power source, and the load (Load being whatever device is being powered). Negative voltage exists between the load and the ground, or negative terminal.
AnswerYour question (and the two answers, above) confuses potential difference with potential. 'Voltage' is synonymous with 'potential difference', not 'potential'.
The two answers, above, are each describing 'potential', not 'voltage'. There is no such thing as a 'positive' or 'negative' voltage in the 'charge' sense. Voltages are absolute, whereas potentials are relative. So, if one point has a potential of +10 V with respect to, say, earth, and a second point has a potential of -15 V, then the voltage (potential difference) between them is 25 V (no sign!).
We can, on the other hand, apply signs to voltages if those signs are used to describe 'sense' or 'direction' in which a voltage is acting. For example, if two batteries are wired in opposition, we can say that the second voltage is acting a 'negative' sense to the first voltage.
We do this when we apply Kirchhoff's Voltage Law to a series circuit, when we write an expression such as: V1 +V2 -V3 = 0
In the above equation, we are saying that voltages V1 and V2 are acting in one direction, while voltage V3 is acting in the opposite direction.
Wiki User
∙ 12y ago
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What is the algebraic sum of the voltages round a loop in a circuit?
Use Kirchoff's law.
What is positive and negative dc voltage?
They are opposites of each other. This refers to the direction of the electrical current is flowing. A battery right side up has +4.6 volts across it. Current is flowing out of the top and I to the bottom. Flip it upside down, now measured the same way you'll see -4.6 volts, meaning current if flowing into the top and out of the bottom.Additional AnswerThere is no such thing as a 'positive' and 'negative' voltage if you are referring to 'positive' and 'negative' in the sense of polarity or charge. Voltage is simply another name for potential difference, and you cannot have a positively- or negatively-charged potential difference! Presumably, what your question should ask is "What is positive and negative potential?".The potential at any point in a circuit is measured with respect to another point in the same circuit -often, this is earth (or ground). For example, a car battery's negative terminal is usually earthed to the vehicle's metal chassis, so anything connected directly to its positive terminal has a potentialof +12 V.On the other hand, 'positive' and 'negative' can also refer to sense or direction, rather than polarity or charge. Used in this sense, you can apply these terms to potential difference or voltage. For example, if a second battery acts in the same direction as another battery, then its voltage is acting in the positive sense (or direction); if it is connected to oppose another battery, then its voltage is acting in the negative sense. Applying the terms 'positive' and 'negative', in this sense, to potential differences or voltages, is useful in various electrical theorems, such as Kirchhoff's.
How does electrical current flow in a circuit?
There is a potential difference (voltage) between two points and a path for electrons to travel from an area of low potential (negative) to an area of high potential (positive). Note the direction of "current flow" is opposite the direction of electron flow. In other words current flows from positive to negative. In a circuit involving only a resistor, the current flowing in the circuit is given by I=V/R where I = current, V= voltage, and R=resistance.
What are normally open and close circuits?
The electric path which starts from the positive terminal of a cell or battery ends at its negative terminal, without any break, is called closed electric circuit or complete electric circuit. The electric path,which starts from the positive terminal of a cell or battery, is broken at some point, is called open electric circuit or incomplete electric circuit.
How current electricity moves in a circuit?
You need a source of electrical potential difference, also known as voltage (which is the technical term for what for you call "electric pressure"). The easiest and most common voltage source is a household battery. Hook up the positive electrode of the battery using a conductor (eg. a copper wire) to one end of your circuit and the negative electrode to the other end, and voila, you'll have electric current flowing through your circuit.
Can Voltage dividers can provide only positive output voltages?
Voltage dividers can provide anything between VCC (the most positive voltage in the circuit) and VSS (the most negative voltage in the circuit). For example, if VCC =0 and VSS = -15, then the output voltage has to be negative. ========================
Does electricity travel from positive to negative or negative to positive in a circuit?
It goes negative to positive.
Positive logic in a logic circuit is one in which?
In Positive logic, we all assume that the more positive (binary) voltage state is One, the less positive voltage state is Zero.Both voltage states could be positive, both could be negative, or they could be opposite polarities.
Should positive go to positive in a circuit?
No, this will not work. Postitive to Negative/Negative to Positive will work.
Why do some electronic circuits need negative voltages?
Because , in some cases for a negative voltage the circuit components will be biased .
In a circuit where does the current begin?
The current flows from negative to positive.
What terminals do the electrons flow through a circuit?
from negative to positive.
Is the battery in an Sl500 battery positive or negative ground?
Batteries are neither positive nor negative ground. It is the circuit itself that determines the common ground. For example: If I have two circuits, one needing 6vdc negative ground and the other needing 6vdc positive ground, the battery would be installed the same way in both circuits (positive terminal on the battery to the positive connection in the circuit, regardless of whether the circuit is positive or negative ground). The reason for labeling the ground as Positive or Negative has more to do with how the circuit is wired up, than the actual voltage source. The explanation for that is beyond the scope of this answer.
How does a short circuit occaur?
Short circuit occurs when positive and negative terminals are connected directly.
What is the link or bridge between negative and positive area called?
The link or bridge between negative and positive area is called a circuit
Does the 1980 el camino driving lights have positive and negative wires?
All electrical components have positive and negative wires to complete the circuit.
Do voltages vary around the circuit and why?
A: Voltages varies on a circuit because current varies caused by difference in resistance
