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What conclusion can you make about how resistance affects current in a wire?
Wiki User
∙ 11y ago
You can solve Ohm's Law for current.
Ohm's Law: V=IR
Solving for current: I = V/R
In other words, more voltage will cause more current, while more resistance will reduce the current.
Wiki User
∙ 11y ago
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If the voltage is 12 volts and the resistance is 3 ohms what are the amps in this circuit?
Using Ohm's law, we can find the current (I) in a circuit where 3 ohms is the resistance (R) and 12 volts is the appllied voltage (V). [(E) means energy]I = V / R = 12 / 3 = 4 amps.Visit this link http://www.csgnetwork.com/ohmslaw2.html for making Ohm's Law calculations.
Why does a wire get hot when an electric current passes through it?
Because the wire has resistance.The power (number of watts) dissipated by any resistance when current passes through it is(the number of amperes of current)2 multiplied by (the number of ohms of resistance).To reduce the power lost from the wire, the choices are:-- reduce the current passing through the wire-- use thicker wire-- keep the wire as cold as possible.(If the wire is made of the right material, and you make it cold enough,then all of its resistance disappears, and it's called a "superconductor".)
What voltage should be applied to make an electromagnet?
The strength of the electromagnet depends on the magnitude of the current in the coil around it.The voltage required is only what produces the desired current in the coil. Since the coil is nothing butwire, the resistance is quite low, and a relatively small voltage produces a relatively large current.
What is an electrical conductor that has very low resistance to current at low temperatures called?
You're thinking of a "superconductor", but the real definition is far more bold.A superconductor isn't a substance that has "very low" resistance at low temperatures.It's one that has NO resistance at very low temperatures. None whatsoever. I mean, literally,you can make a coil of wire out of this stuff, keep it super-cold, pump an electric current into thewire, and connect the ends together, and the current is still flowing around the coil months later !I know it sounds incredible, but that's exactly what they do every day, in CT and MRI machines.
What would happen if the current passing through the coil was too large?
The coil offers some amount of Resistance to the flow of Electric current through the coil. The Resistance of the coil depends on the material used to make the coil and the thickness of the coil wire ( its gauge ) When a current flows through the coil, the voltage drop across the coil and the Power dissipated in the coil both are proportional to the magnitude of current and the coil resistance. Normally the coil is rated to carry certain current and dissipate certain amount of power without causing any damage. If a large magnitude of current flows through the coil beyond its rating , the voltage drop across the coil and the power dissipation in the coil both increase substantially causing over heating of the coil. This can damage the coil and may result in burning of the coil
What is added to a circuit to make the current smaller?
The reduction of voltage or the increase of resistance will reduce the current in a circuit.
How much current is need for 12 VDC to flow through water?
First thing voltage does not flow current does. Voltage is the potential or pressure needed to make the current flow. Current is directly proportional to the applied voltage and inversely proportional to the resistance of the circuit. To make the current flow you have to adjust the resistance of the circuit and that would be the water in this case. Salt added to water will make the water conductive so the resistance can be adjusted thereby making the current rise or fall depending on the water solution's resistive properties. The equation that you should consider using is Amps = Volts/Resistance.
What happens to an electric current when the wire is made smaller?
Electric current as we usually describe it is the flow of electrons. Current is caused to flow by voltage, which can be looked at as "electrical pressure" that forces electrons to move. Currents can be made smaller or larger by decreasing the voltage across a fixed amount of resistance. As resistance is the quality of "resisting" or "limiting" current flow, we can change resistance to change current. For a give voltage, if we increase the resistance, we can make the current smaller, and if we decrease it, we can make current larger. In electronics, voltage equals current times resistance. E = I x R Also true is that current is equal to voltage divided by resistance. I = E/R As current equals volts divided by resistance, if we change one of them without changing the other, current will change. And in increase in voltage (with no change to resistance) will cause current to go up. The opposite is also true. Also, if we increase resistance (with no change in voltage), current will go down. And the opposite is true here, too.
Formula used to find the maximum current that can be carried by a resistor if resistance and wattage rating is known?
Manipulate the following equation, to make I the subject: P = I2R, where P = power, I =current, and R = resistance.
How could two circuits have the same current but different resistances?
The equation, I=V/R (Current = Voltage/Resistance) determines the current, so if you increase both V and R, you will be able to get the same current (with a bit of adjustment to make it exact)example:10 Volts & 2 Ohms resistance = 5 Amps Current20 Volts & 4 Ohms resistance = 5 Amps Current
Why must you make current flow through the meter in order to measure it?
You don't. ...unless you want to directly measure the current in a circuit branch. That's the purpose of an ammeter. You can also use a volt meter if you know the resistance of a resistor in that branch to determine current (assuming DC circuit here) - current = voltage / resistance. This may be more useful for circuitry that is on a breadboard, since inserting an ammeter may not be practical.
Why do solar cells need to lower resistance in the electrical circuits that make up their electronic system?
Reducing the resistance of solar cells increases the output current. Although the voltage remains the same the current is effected due to internal resistance. A reduction in output current can result in lesser diminished functioning in household appliances.
One way to make current is to use a what?
You can apply a potential difference across a wire to cause a current to flow through. Ohm's Law allows you to calculate the amount of current based on the voltage supplied and the resistance of the circuit. I = current V = voltage or potential difference R = resistance I = V/R
What do you mean by 'cold resistance' and 'hot resistance'?
Metals that make up typical resistors (and many other electrical components for that matter) tend to heat up as current flows through them. "COLD" resistance is the resistance before it is operating and "HOT" resistance is the resistance after some operating time has elapsed.
How many volts will it take to make 12amps go through 3 ohms of resistance?
It will take 36 volts to make 12 amps go through 3 ohms of resistance. Ohm's law states that the current in amperes is equal to voltage over resistance.
How can convert voltage source into current source?
Take the internal series resistance of the voltage source and make it the internal parallel resistance of the current source. Then compute using Ohm's law the current of the current source to be equal to the maximum current the original voltage source could supply a short circuit load. Note: the two sources are equivalent.
Why internal resistance of an ideal voltage source is zero and an ideal current source is infinty?
Current source means current generator for a circuit. An ideal current source gives all current to the circuit, but practically a current source does n't give all current to the circuit, instead, a source resistor is connected in parallel to the current source to indicate the current drop.
