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What effect if any does connecting a voltmeter across a resistor in a circuit have on the current through resistor?
EnricoVialligp6675
A very very tiny amount of the current that would normally flow through the resistor instead flows through the voltmeter, allowing it to make its measurement. For most purposes this very very tiny amount of current can be completely ignored.
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∙ 9y ago
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How is an ammeter converted to a voltmeter?
The ammeter is used in series, because you want to measure the current through a circuit. The voltmeter is used in parallel, because you want to measure the voltage across a circuit. If you were to place the voltmeter in series, no current would flow because of the relatively high impedance of the voltmeter. If you were to place the ammeter in parallel, you would create a short-circuit, due to the relatively low impedance of the ammeter.
How does an ammeter work?
An ammeter is a low voltage voltmeter in parallel with a small resistance resistor. Current flow through the resistor creates a voltage drop across it which is then measured by the voltmeter.
A can be used to reduce the current in a circuit?
A resistor.
What is series dropping resistor?
A series dropping resistor is a resistor that limits the amount of current flow in a circuit.
What is the function of the resistor in an led circuit?
current limiter.
What effect if any does connecting a voltmeter across a resistor in a circuit have on the current through the resistor?
A very very tiny amount of the current that would normally flow through the resistor instead flows through the voltmeter, allowing it to make its measurement. For most purposes this very very tiny amount of current can be completely ignored.
What path will the current takes in a series circuit with a voltmeter pause does the current goes through voltmeter pause because if it does pause isn't current suppose to be taking the shortest path?
A voltmeter is designed to operate like a very large resistor (order of megaOhms), in parallel to the circuit that it is measuring. As long as the voltmeter resistance is much larger than the circuit that it is measuring, it will draw very little current away from the circuit and will only minimally disturb the operating circuit. See related link. If the voltmeter is connected in series with the rest of the circuit, then that is the same as connecting a very large resistor in series.So for example if you have 10 volt battery and a 10 ohm resistor, that would be 1 amp (without the voltmeter). Now if the voltmeter is 10 megaohm, the total resistance is 10000010 ohms, so the current is 0.999999 microamperes, and the voltage across the 10 ohm resistor is 9.99999 microvolts, while the voltage across the voltmeter is 9.999990 Volts (these numbers are rounded, but you get the idea).Suppose you put in series with a 1 kiloOhm (not sure about that spelling) resistor. The total resistance is 10001000 ohms, and current is 0.99990 microamperes, the voltage across resistor is now 0.9999 millivolts (it was microvolts) and the voltage across the voltmeter is 9.9990001 volts
What effect if any does connecting an ammeter in series with a resistor in a circuit have on the current though the resistor?
That depends on the quality (price) of the meter. Ideally it should have no effect.
How do you convert voltmeter to ohmmeter?
First you will need a constant current source. Do NOT connect the voltmeter to the constant current source without the resistor to be measured already connected. Do NOT use a battery, it is a voltage source. Then follow these steps to measure a resistor:connect the voltmeter across the resistor to be measuredconnect the voltmeter-resistor combination across the constant current sourceread the voltmeter and record the voltagedisconnect the voltmeter-resistor combination from the constant current sourcedisconnect the voltmeter from the resistorcalculate the resistance from the measured voltage and current from the source with Ohm's law in this form: R = V ÷ IIts much easier to just use the ohms setting on a multimeter.
How does an ammeter work?
An ammeter is a low voltage voltmeter in parallel with a small resistance resistor. Current flow through the resistor creates a voltage drop across it which is then measured by the voltmeter.
How is an ammeter converted to a voltmeter?
The ammeter is used in series, because you want to measure the current through a circuit. The voltmeter is used in parallel, because you want to measure the voltage across a circuit. If you were to place the voltmeter in series, no current would flow because of the relatively high impedance of the voltmeter. If you were to place the ammeter in parallel, you would create a short-circuit, due to the relatively low impedance of the ammeter.
How do you install a resistor in an DC circuit?
It depends on the purpose for installing the resistor. If the intent is to decrease current flow, the resistor must be connected in series with the load. If the purpose is to increase current flow, the resistor must be connected in parallel with the load. To connect a resistor in series, connect the resistor to one side of the power source, in line with the load. This will decrease circuit current flow. To connect a resistor in parallel, connect the resistor between the positive and negative sides of the power source, which will effectively connect the resistor across the load . This will increase current flow through the circuit. However, before connecting a component in parallel, make sure the increase in current flow will not exceed the current rating of the circuit or fuses/breakers will blow.
A can be used to reduce the current in a circuit?
A resistor.
Can a short-circuit be detected by voltmeter?
yes, voltmeter drops to zero as current increases to maximum
Why do you get different results when calculating the voltage drop across a resistor and ignoring resistance of a voltmeter and when considering it?
Voltage drop is the product of current and resistance. When you connect a voltmeter across a resistor, you are connecting that voltmeter's internal resistance in parallel with that resistor. The resulting resistance of this parallel combination is lowerthan that of the resistor. As a result the voltage drop (current times this lower resistance) will be lower than it would be without the voltmeter connected. This is called the 'loading effect' of that voltmeter.The higher the internal resistance of the voltmeter, the less effect it will have on lowering the overall resistance when connected across a resistor. This is why the internal resistance of a voltmeter is made deliberately very high. Under most circumstances, therefore, a conventional voltmeter will have very little effect on the resistance of the circuit being tested and, so, it will have no significant effect on the voltage appearing across the resistor.However... for circuits that already have exceptionally-high resistance values, you must be careful when you select a voltmeter as you must take into account its internal resistance and ensure the voltmeter you use has the very highest internal resistance available. This is because the loading effect increases with circuits that have a high resistance. That might involve selecting a voltmeter that works on a completely-different principle , such as an electrostatic voltmeter or, perhaps, an oscilloscope
How can you say that ammeter measures current and voltmeter measures voltage?
voltmeter in parallel and ammeter in series of a circuit.
Does a resistor only decrease current in a circuit?
A resistor does not only decrease current in a circuit it can also reduce tension(voltage) if connected in series.
