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Of course. A good voltmeter can be applied across anything, since its impedance
is high and its presence has no effect on the operation of the circuit. When it's
connected across a variable resistor, the voltmeter most likely reveals a changing
voltage as the resistor is varied.
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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
How can loading effect affect voltage measurement in a circuit?
Suppose you have two 100 kilo Ohm resistors in series across a 12 volt supply.The expected and actual voltage at their junction is 6 volts. Now measure the voltage across one resistor with a Voltmeter. The instrument must take a little power to move the meter needle or be taken by the digital circuitry. If the input resistance of the voltmeter is 100 Kilo Ohms then it will make that resistor under test appear to be 50 Kilo Ohms. The voltage across the resistor drops to 4 Volts. This is the loading effect of the voltmeter.
What is the rule for voltage across each resistor?
Volt across a resistor = resistance x current through the resistor.
How do you connect an ammeter and voltmeter?
The voltmeter is connected across the supply and the ammeter is connected in series with the supply.
The voltage drop across a resistor is 1.0 V for a current of 3.0 A in the resistor what is the current that will produce a voltage drop of 9.0 V across the resistor?
The resistor is 1/3 of an ohm. A 9 volt drop across the resistor would cause a draw of 27 amps through the resistor. The wattage you would need for that resistor is at least a 243 watts.
Voltmeter is connected in parallel with resistor?
A voltmeter can be connected in parallel with a resistor to show the voltage across the resistor.
How is the potential difference across a resistor measured?
by using voltmeter
How are you going to arrange a circuit if you want to measure the potential drop across a resistor?
Connect a power source to the resistor (+ve terminal to one side of the resistor and -ve terminal to the other) then connect a voltmeter in parallel with the resistor. The reading on the voltmeter will provide a measure of the potential difference across the resistor (ie: the voltage drop across it).
How measuring amps?
A; By using a voltmeter across a small shunt resistor
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 should voltmeter be connected to measure the potential difference across a resistor - in series or in parallel?
In parallel.
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
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 are two familiar mistakes when using an ohmmeter and a voltmeter?
Voltmeter connect in parallel with the circuit setting on voltmeter highest range first then to lower range. Ohmmeter we need to use the ohmmeter meter setting connect across the resistor
What is the procedure to improve the voltage range of voltmeter?
A: by adding a big value resistor from the source while measuring across a low value
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.
