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When a Resister is jumpered out what is the voltage across the resistor?
Wiki User
∙ 15y ago
A Resistor [note spelling] when jumpered-out has a theoretical resistance of zero. The voltage across same is zero.
To "jumper-out" is presuming a wire across the resistor: Theoretically this "ideal" wire has zero resistance, however, in practice a "thin" copper wire of (say) 10mm length - e.g., about the length of a 1/8th-watt resistor - would have a resistance around the milliohm.
Depending on the current passing through a wire (per V=IR) the voltage might be nothing or a mega-volt, as a function of the current and cross-section of the wire.
However, anything over, say, a small number of amps through a real-world "thin" wire would cause the wire to act as a fuse and break, so, in the case of a thin wire (0.25 mm say) we're looking at near zero volts across the resistor/wire combination at say 0.01 Amps and tending the supplied voltage at, say, 10 amps.
If, on the other hand, the resistor is no longer in the circuit (literally "jumpered out") then the theoretical resistance of the "gap" where the resistor should be is infinity (real-world: The order of megaohms). The makes the voltage across same just about the voltage supplied to either side of said resistor as if it were not there, which will depend on the rest of the circuit.
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∙ 15y ago
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If the resistance in the circuit is increased what will happen to the current and voltage?
* resistance increases voltage. Adding more resistance to a circuit will alter the circuit pathway(s) and that change will force a change in voltage, current or both. Adding resistance will affect circuit voltage and current differently depending on whether that resistance is added in series or parallel. (In the question asked, it was not specified.) For a series circuit with one or more resistors, adding resistance in series will reduce total current and will reduce the voltage drop across each existing resistor. (Less current through a resistor means less voltage drop across it.) Total voltage in the circuit will remain the same. (The rule being that the total applied voltage is said to be dropped or felt across the circuit as a whole.) And the sum of the voltage drops in a series circuit is equal to the applied voltage, of course. If resistance is added in parallel to a circuit with one existing circuit resistor, total current in the circuit will increase, and the voltage across the added resistor will be the same as it for the one existing resistor and will be equal to the applied voltage. (The rule being that if only one resistor is in a circuit, hooking another resistor in parallel will have no effect on the voltage drop across or current flow through that single original resistor.) Hooking another resistor across one resistor in a series circuit that has two or more existing resistors will result in an increase in total current in the circuit, an increase in the voltage drop across the other resistors in the circuit, and a decrease in the voltage drop across the resistor across which the newly added resistor has been connected. The newly added resistor will, of course, have the same voltage drop as the resistor across which it is connected.
What is the volt drop across a 10k resistor with a 5 volt supply?
If there is nothing else in the circuit, then the voltage drop across the resistor will be the full supply voltage of 5 volts. The size of the resistor does not matter in this case - it will always be 5 volts.
Why common emitter amplifier gives phase reversal?
A: Because it is a voltage amplifier the current will inversely reflect the voltage across a resistor
What instrument measures current and voltage?
Voltmeter.Current and voltage are two different things. They are closely related but a current does not imply a voltage and nor does a voltage imply a current.A volt meter is used to measure a voltage. The voltage may be across a battery or other power source. It may be across a component such as a resistor or a group of components. If a current is flowing through a resistor, there will be a voltage across the resistor. Similarly, if there is a voltage across a resistor, there will be a current flowing.Current is measured using an ammeter - Current is measured in amps, hence the name of the meter.The two meters together can be used to analyze most electronic circuits and they are the two most important items of test equipment in electronics. Devices called multi-meters are combined ammeters and voltmeters and are in every electronics engineer's toolbox.
Why 250 ohm resistance using for transmitter calibration?
In this situation, to calibrate a transmitter you need a power circuit and communicator circuit. The Hart communicator used in the calibration process is connected to the power source circuit in parallel. The power source circuit is the one that has ammeter, 250 Ohm resistor, and power source all connected in series. As the transmitter sends output mA, it creates volt drop across the 250 Ohm resister. Let's say the volt drop across the resistor was 1 Volt. Now, back to the Hart communicator. It is a load, meaning there will be a volt drop across the Hart communicator. Since it is in parallel with the power circuit, it is also parallel with the resistor. So, the 1 volt drop across the 250 Ohm resistor will also make 1 volt drop across the Hart communicator. Technically speaking, the 1 volt drop across the Hart communicator is only true if its resistor is also 250 Ohm. However, it does NOT matter what voltage drop is in the Hart communcator. It only sees the "relative" voltage drop changes to measure the changes in transmitter outputs.
Does voltage flow across or through a resistor?
No. If a voltage is applied across a resistor, a current flows through it.
How measure the value of resister?
To measure the value of a resistor, apply a voltage and measure the voltage across the resistor and the current through the resistor. Use Ohm's law: Resistance equals Voltage divided by Current. Start with a small voltage and increase gradually until a reading is obtained, but be careful that the power dissipation (watts = volts times amperes) of the resistor is not exceeded. Simpler solution: Use an ohmeter.
Does a resister use current?
It may be better to say that a resistor allows current flow through itself rather than to say that a resistor is a device that will "use" current. It does "resist" current flow, and thus limits it to some degree depending on its resistance. (More resistance means more limiting of current flow.) The resistor "drops voltage" as well limits current. A resistor "feels voltage" from some source, and the voltage it "feels" is said to be the "voltage drop" of the resistor. The voltage drop is the voltage that could be measured across that resistor with a meter.
What is a maximum voltage across a resistor?
The voltage across the resistor is whatever voltage is applied. The only maximum here would be a voltage that would damage the resistor. If you think this might happen, you'll have to look up such a voltage from the data sheets.
What is leakage resistance?
leakage resistance of a resister is type of fault which occurs at a specific voltage across the resister which are undertesting.
What is the rule for voltage across each resistor?
Volt across a resistor = resistance x current through the resistor.
In a series circuit why does the largest voltage drop occur across the largest or smallest resistor?
It doesn't. In a series circuit, the largest voltage drop occurs across the largest resistor; the smallest voltage drop occurs across the smallest resistor.
What is a protective resistor?
The protecting resistor is put in series with the LED so that you have a voltage divider - the supply voltage is split across the LED ( max 0.6v) and the remainder across the protecting resistor. So if your supply is 6volts, 5.4v will be across the resistor,
Does current flow through a resistor or across a resistor?
Normally through the resistor's internal construction. It flows through any part of the resistor that has low resistance- be it anywere. And then there's this. It might be that one should consider that current flows through a resistor and voltage is dropped across a resistor. Perhaps this is where the question began. The former is fairly straight forward. The latter can be vexing. Voltage is said to be dropped across a resistor when current is flowing through it. The voltage drop may be also considered as the voltage measureable across that resistor or the voltage "felt" by that resistor. It's as if that resistor was in a circuit by itself and hooked up to a battery of that equivalent voltage.
What is a 1.5 omega resister?
The capital Greek letter Ω (omega) is the symbol for Ohms - the unit of resistance. A 1.5Ω resister is a resistor with quite a low resistance. If a voltage of 1.5 Volts is applied across it, a current of 1 Amp[ere]s will flow through it.
What is the current drop across the resistor?
The correct question is what is the voltage drop across a resistor or the current flowing through the resistor using Ohm's Law where Voltage = Current x Resistance
Is current is drop when it flowing through the resistor?
Current flows in loops, voltage drops across elements. With relation to current, what flows in, must flow out, so no, current is not dropped across a resistor, it flows through a resistor and voltage is dropped across the resistor.
