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Why a high input impedance device is generally needed to measure the hall voltage?
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What is a tachogenerator in control system?
a device to measure rotation speed of a shaft as a proportional voltage
Why is it that a voltmeter is not connected parallel in a circuit?
An ammeter is connected in series with the circuit being measured because you want to measure the current flowing through the circuit, whereas a voltmeter is connected in parallel with the circuit being measured because you want to measure the voltage across the circuit. Kirchoff's current law states that the signed sum of the currents entering a node is zero. A consequence of that law is that the current at every point is a series circuit is the same. The ammeter measures that current and, so long as its impedance is not too high, it won't disturb the circuit being measured. Kirchoff's voltage law, on the other hand, states that the signed sum of the voltage drops in a series circuit adds up to zero. A consequence of that law is that the voltage across parallel nodes must be equal. The voltmeter measures that voltage and, so long as it impedance is not too low, it won't disturb the circuit being measured. Formalities aside... An ammeter is a low impedance device. If you were to connect it in parallel with a circuit, it would draw all of the available current from that circuit. It and the circuit or its power supply would be damaged, because the ammeter represents a short circuit. A voltmeter is a high impedance device. If you were to connect it in series with a circuit, it would prevent any of the available current from reaching that circuit. While it and the circuit would probably not be damaged, the circuit would not function. Since practical meters are not perfect, the ammeter is not zero ohms impedance, nor is the voltmeter infinity ohms impedance. If you intend to measure both current and voltage in a circuit, it is normal protocol to measure the voltage across the circuit downstream of the ammeter, so that you would not be also measuring the additional voltage drop across the ammeter.
Why is a voltmeter not placed inside the circuit?
The voltmeter is connected parallel to the circuit in order to measure the voltage drop across that circuit or sub-circuit. If you were to connect the volmeter series to the circuit, since it is a high impedance device, it would represent an effective open-circuit condition. You would see the voltage available to the circuit, but the circuit would not receive its intended current and it would not function. Contrast this with the ammeter, which you do place series to the circuit in order to measure the current flow through the circuit.
What is an electrostatic discharge and why does it occur?
A VERY BIG PROBLEM practically all electronics are restricted to voltages no greater 40 50 volts electrostatic can be as much as 5kv to 50 kv but the source impedance is very hi so while the voltage is there current capabilities are not a low impedance device can possibly survive these discharges but a hi impedance device like MOS cannot survive since the negligent current will raise the potential very hi blowing the device.
How do you measure the capacitance of 3 phase capacitor in active line voltage of 3 phase circuit?
You measure the capacitance of a capacitor in an active circuit by observing the voltage across it and the current through it. That gives you, by Ohm's law, the impedance of the capacitor. Plug that in the the equation for capacitive reactance, and you get capacitance. Note: There is no such thing as a three phase capacitor. A capacitor is a two terminal device that resists a change in voltage inversely proportional to its capacitance. You connect one capacitor to one phase. If you have a "three phase capacitor", then you are talking about three capacitors. Deal with each one separately.
What necessary condition must a voltage measuring device satisfy?
The most essential element in a voltage measuring device is a very high impedance. This prevents the device interfering with the measurement.
What device has the smallest current in parallel circuit?
The one with the highest resistance (or impedance, if the voltage is not DC).
Can an impedance matching device reduce electrical costs?
An impedance matching device is used to test the resistance, inductive reactant and capacitive reactant in a circuit. If one component did not match the impedance of the conductor, some of the current will be lost by the conductors itself. In conclusion if electricity is lost, the component needs to meet its regular voltage. It consumes more voltage than expected because of the loss. Impedance matching device can actually reduce electrical cost.
Why is impedance matching used in electronics?
Impedance matching is used in electronics to get an electronic device with an input and output source to work. Impedance matching will give the electronic it's maximum transfer of voltage. An example of this are FM radio receivers.
How to find resistance?
-- Apply a small, known voltage between the terminals of the device. -- Measure the current through the device with the voltage applied. -- Calculate the resistance of the device. It's (voltage) divided by (current).
What is a tachogenerator in control system?
a device to measure rotation speed of a shaft as a proportional voltage
What is sencer?
If you mean sensor, a sensor is a device that changes based on some phenomenon and this change is used to measure the change in the phenomenon.For example, assume a device produces a voltage and the amount of that voltage depends on the temperature of the device. It can be used as a sensor for temperature. Assume you put the device in water and another device measures the voltage produced by the sensor. Based on the voltage of the sensor it can display the temperature of the water. So, in this example, the sensor senses the temperature of the water.
What is a sencer?
If you mean sensor, a sensor is a device that changes based on some phenomenon and this change is used to measure the change in the phenomenon.For example, assume a device produces a voltage and the amount of that voltage depends on the temperature of the device. It can be used as a sensor for temperature. Assume you put the device in water and another device measures the voltage produced by the sensor. Based on the voltage of the sensor it can display the temperature of the water. So, in this example, the sensor senses the temperature of the water.
Why is JFET used as an input device?
it has high input impedance
What is the function of the voltmeter in an electric circuit?
A voltmeter is a device to measure the voltage in a electric circuit, and must have be connected in parallel to it.
Why is it that a voltmeter is not connected parallel in a circuit?
An ammeter is connected in series with the circuit being measured because you want to measure the current flowing through the circuit, whereas a voltmeter is connected in parallel with the circuit being measured because you want to measure the voltage across the circuit. Kirchoff's current law states that the signed sum of the currents entering a node is zero. A consequence of that law is that the current at every point is a series circuit is the same. The ammeter measures that current and, so long as its impedance is not too high, it won't disturb the circuit being measured. Kirchoff's voltage law, on the other hand, states that the signed sum of the voltage drops in a series circuit adds up to zero. A consequence of that law is that the voltage across parallel nodes must be equal. The voltmeter measures that voltage and, so long as it impedance is not too low, it won't disturb the circuit being measured. Formalities aside... An ammeter is a low impedance device. If you were to connect it in parallel with a circuit, it would draw all of the available current from that circuit. It and the circuit or its power supply would be damaged, because the ammeter represents a short circuit. A voltmeter is a high impedance device. If you were to connect it in series with a circuit, it would prevent any of the available current from reaching that circuit. While it and the circuit would probably not be damaged, the circuit would not function. Since practical meters are not perfect, the ammeter is not zero ohms impedance, nor is the voltmeter infinity ohms impedance. If you intend to measure both current and voltage in a circuit, it is normal protocol to measure the voltage across the circuit downstream of the ammeter, so that you would not be also measuring the additional voltage drop across the ammeter.
What is effect on amplifier output if you increase input impedence?
Impedence is synonymous with resistense. Greater the I, lesser the outputNo.First, it's *resistance* and *impedance*.Now, if the amplifier is a current amplifier, the above makes sense. (higher Zin, less Iin for a constant Vin).But if it's a purely voltage amplifier, it only responds to the input voltage, so the impedance (so long as it's not affecting the source/driving device) will have no effect on a purely voltage-amplifying amplifier.
