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It depends on the application. Voltmeters have a high internal resistance, while ammeters have a low internal resistance.
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∙ 12y ago
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Do Dead batteries have high internal resistance?
yes, batteries have high internal resistance. The higher the resistance the lower power you get out of the batter. Therefore if you no power you have very high resistance.
Why does voltmeter have high internal resistance?
No, ammeters have a low internal resistance. This is so that when they are put in series with a circuit, they change the circuit's operating characteristics as little as possible.Contrast this with voltmeters, which do have a high internal resistance, and which are intended to be placed in parallel with the circuit they are measuring.Use the link below to the related question on why ammeters have a low internal resistance and read through that information to see why things are the way they are.
Is it desirable for a battery to have a high internal resistance?
No, it is desirable for a battery to have a low internal resistance.
What wire connection better high or low resistance?
Usually low resistance is better.
Why should you be the internal resistance of the very few Amitr?
ammeter connect in series in circuit to measure the current, if the Ammeter have a high resistance it would effect the voltage value because there will be a drop voltage over the internal resistance of the Ammeter, so we desgin the ammeters with very low resistance...
When Replacing 12v coil on 1998 Kubota engine wg750 could it have resistance type external wiring from coil to distributor or is resistance internal in coil?
A engine coil has a high internal resistance, the needing of a suplementar resistance may be advised to you by a car electrician, who works with such brand and model of your car.
Why are there more than two terminals on some ammeters and voltmeters?
A volt meter needs a high internal resistance not to influence the measurement, an ammeter needs a low internal resistance. Sometimes the easiest way to make that happen is to have different connectors.
The internal resistance of ammeter is?
The internal resistance of an ideal voltmeter is infinity ohms. The internal resistance of an ideal ammeter is zero ohms. Since there are no ideal voltmeters or ammeters, we consider the error introduced by adding these instruments to various circuits. In general, practical meters have high enough impedance (voltage) or low enough impedance (current) to not affect the reading more than the instruments accuracy specification, or to not affect the circuit more than is considered acceptable. There are times when this is not true, so we always consider the instrument and its contribution to systemic error.
How does the loading effect of an ammeter in a low resistance circuit compare to the loading effect in a high resistance circuit?
The voltmeter has an internal resistance, which should be as high as possible. As this resistance draws current from the circuit under test, it will affect circuit operation. This is more pronounced in a high impedance circuit because the current drawn flows through higher resistances.
Battery connected to high Resistance voltmeter the reading is 1.5V when it is shorted on a low resistance ammeter the current is 2.5A what is the emf and the internal resistance of the battery?
The Thevenin equivalent circuit of this battery is 1.5V and 0.6 ohms in series. A more exact answer cannot be given without knowing the actual resistance of the 2 meters (I assumed infinite for the voltmeter and zero for the ammeter, as would be for ideal meters).However I would NEVER attempt this test as you describe it, many types of batteries will explode like bombs when shorted (as they would be when an ammeter was placed across them)! The correct way to do this test safely is with just a voltmeter and an adjustable high wattage resistor.
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
Why the internal resistance should be high in operational amplifiers?
High input impedance implements the operation of the external feedback circuitry (e.g. diff. amplifiers vs. comparators).
