Questions about series voltmeters in circuits

Ignoring the internal resistance of the power supply, wire resistance, etc., the answer is definitely not 6, it must be smaller than 6. Because the sliding rheostat has resistance and needs to divide the voltage, but the internal resistance of the voltmeter is relatively very large, and the resistance of the rheostat is small, so the varistor divider voltage is very small, and the voltmeter divider voltage is very large. It's like a total of 10 billion dollars of wealth, you share it with another person, but he only gets 1 cent, and the rest is yours, what's the difference with everything being yours?

Therefore, despite the partial voltage, the voltmeter measures the electromotive force of the power supply.

No matter how much the resistance is 6, because the resistance of the voltmeter is infinite, it can be regarded as an open circuit in the circuit, so the maximum resistance of the general slip can be washed and slept in front of it, of course... If the slip resistance is large enough to be pk with the voltmeter (this strange situation is generally told in the question), that's another thing, and this strange situation can be replaced by two voltmeters in series unless the questioner's brain is pumped. . . One year the college entrance examination question was like this, the power supply voltage is the sum of the voltages of two voltmeters.

Regardless of its resistance value, it is 6

Voltmeters are connected in series.

It is equivalent to a broken circuit.

There is no current. The voltage on the sliding rheostat is 0

What is measured is the supply voltage.

The voltmeter is also equivalent to a resistor, but the internal resistance is relatively large, so when you are connected in series with the resistor, it is the voltage divider, if your resistance is small, it can be basically ignored, if the resistance is large, then the voltage will definitely drop.

What is connected in series with the voltmeter, if the power supply, sliding rheostat, and voltmeter are connected in series, then the voltmeter is naturally 6V

The power supply and the sliding rheostat are connected in series, and the voltage change is the measured power supply voltage.

Is your voltmeter connected to**?

VoltmeterSeries in a circuit measures the voltage across the power supply.

To judge the object measured by the voltmeter, do not include the electrical appliances and the power supply together, for example, the voltmeter and the small bulb are connected in series, and the voltage of the small bulb is not measured, the voltmeter measures the voltage at both ends of the power supply.

The method of measuring the object of the voltmeter.

1. Short-circuit grip method.

The voltmeter is removed, assuming that the wire is connected to the position, if some electrical appliances or power supplies are short-circuited at this time, these electrical appliances or power supplies are the objects of the voltmeter's measurement.

2. Desourced method.

Remove the "power supply" (cover the power supply with your hands), and then see which part of the voltmeter forms a closed loop, then the voltmeter measures the voltage of that part of the circuit.

3. Slip Zen return method.

The two ends of the voltmeter slide along the connected wires to both ends of the appliance or power supply.

The device is regarded as a new battery, and the internal resistance = the resistance value of the internal resistance of the battery itself when it is connected in parallel with the voltmeter. The voltmeter only needs a tiny amount of current, about a few milliamps, to work.

All electrical appliances are not working, and the ammeter has no indication, only the voltmeter on both sides of the breakpoint has an indication, and the first guess is close to (or equal to) the power supply voltage.

The part of the electrical appliances that are short-circuited does not work, and the ammeter has an indicator, the voltmeter connected to both ends of the short-circuited electrical appliances has no indicator, and the voltmeter connected to both ends of other electrical appliances has an indicator.

A voltmeter is an instrument that measures voltage. The structure of the voltmeter is as follows: there is a permanent magnet in the sensitive galvanometer, and a coil composed of wires is connected in series between the two binding posts of the galvanometer, and the coil is placed in the magnetic field of the permanent magnet and connected with the pointer of the meter through the transmission device.

Commonly used voltmeter - voltmeter, voltmeter symbol: V, most voltmeters are divided into two ranges filial mode. The voltmeter has three binding posts, one negative binding post, two positive binding posts, the positive pole of the voltmeter is connected with the positive pole of the circuit, and the negative pole is connected with the negative pole of the circuit.

The voltmeter must be connected in parallel with the appliance under test. The voltmeter is a fairly large resistor, ideally thought of as an open circuit. The voltmeters commonly used in laboratories at the junior high school level have ranges of 0 3 V and 0 15 V.

When voltmeters with different internal resistance are connected in series, the voltage with large internal resistance is higher than the voltage with small internal resistance. The sum of the measurements of the two voltmeters is equal to the voltage being measured.

A voltmeter is an instrument that measures voltage. It is composed of permanent magnets, coils, etc. The voltmeter is a fairly large resistor, ideally thought of as an open circuit. The voltmeters commonly used in laboratories at the junior high school level have ranges of 0 3 V and 0 15 V.

Principle:

Traditional pointer voltmeters and ammeters are based on one principle, which is the magnetic effect of electric current. The greater the current, the greater the magnetic force generated, the greater the swing of the pointer on the voltmeter, there is a magnet and a wire coil in the voltmeter, after passing the current, the coil will produce a magnetic field, and the coil will be deflected under the action of the magnet after being energized, which is the head part of the ammeter and voltmeter.

Because the voltmeter should be connected in parallel with the measured resistance, if the sensitive galvanometer is directly used as the voltmeter, the current in the meter is too large, and the meter will be burned out, so that a large resistance needs to be connected in series in the internal circuit of the voltmeter, so that after the transformation, when the voltmeter is connected in parallel in the circuit, due to the effect of resistance, most of the voltage added to both ends of the meter is shared by the resistance in series, so the current through the meter is actually very small, so it can be used normally.

The symbol of the DC voltmeter should be added with a " under v "The symbol of the AC voltmeter should be added with a wavy line under v ".