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The simple answer is you can't. However, there may be other ways to calculate it.
If you know the voltage rating (E) and wattage rating (P, for Power) of the item, such as a light bulb, you can calculate the expected current (I) of the item using the formula P = IxE and then substituting the current into the formula E = IxR to calculate the resistance (R). Simple high school algebra will solve these equations.
If an item is not rated in watts it may be rated in volt-amps (VA) which can be used in the same formulas in the place of P.
Some items, such as flourescent lamps, motors, electronics, anything with a ballast, etc. etc., are not purely resistive so calculating resistance is meaningless for practical purposes.
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What is transducer and how it may be used to measure displacement?
Transducer is a device which convert physical signal into electrical signal ( current/voltage/resistance). for linear measurement we can use LVDT (Linear Variable Displacement Transducer/ Linear Variable Differential Transformer). and for rotary measurement we can use RVDT (Rotary Variable Differential Transformer)
Define Internal Resistance?
The internal resistance of a device is the resistance in ohms of that device. It is the resistance electrons need to overcome before electricity is said to flow.
What check should be done to an electrical measuring device before attempting to measure electrical resistance?
An electronic measuring device also known as a multimeter is used to check the electrical voltage in homes and industrial areas. The checks that need to be done before a multimeter is used is the to plug the black test lead into the black socket marked com. The red lead plugs into the red socket marked voltage and resistance.
What is described as a device with specific resistance and is used to control current?
A current shunt is a device with a very low resistance, usually around one ohm. The exact resistance of the shunt is printed on the device for reference, and it is often slightly higher or lower than nominal, for example a 1 ohm shunt may actually have a resistance of .99986 ohms or 1.0002 ohms. A current shunt is not used to control current, however, so I do not know if this is the device you are asking about. It is used to measure current by using a precision voltmeter to measure the voltage drop across the shunt, and then using ohms law to calculate the current. Voltage (Volts) divided by Resistance (Ohms) equals Current (Amps). When the shunt is placed so that it interrupts a circuit, (placed in series), the current flowing in the circuit can be accurately measured with the shunt, without changing the values in the circuit enough to affect it. Many shunts of this type have a large heavy duty resistor that does not overheat easily. The shunt should also have a max current rating listed on it.
How do you measure electrical insulation resistance value?
By Megger testing (meggering) of the motor any one can measure the IR of the motor. MEGGER is a device used to measure IR. Analog Megger device may generate 500 volts..it gives coil to coil or coil to body IR value...it should not be less than 2 Mega ohm, generally it should be or kept more than 5 mega ohm...thanks ...DEEPAK RAJPUT
How do you measure deterioration of copper amapacity or resistance as stranded copper cable heats or ages Is their a device to do this?
The proper way to do this is to measure the voltage from end-to-end while a known current flows through it. Measuring the resistance directly is often very hard without special equipment (which does the measurement as described above).
What is the name of the device that measures resistance?
Most multimeter are able to measure resistance.
What device is used to measure the resistance of a resistor?
You can use a multi-meter to measure resistance. The specific portion of the meter for measuring resistance is called an ohmmeter.
What does a Nuclear radiation device measure?
The device is called a Geiger counter and it has a measurement scale in Microsieverts.
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).
Which measurement is a reading from a sphygmomanometer?
A sphygmomanometer is a device used to measure blood pressure. A more common name for this device is a blood pressure meter.
What word with a Greek root means a measurement device for distance traveled?
The word for this device is an "odometer" from the Greek roots hodos (path) and métron (measure).
What is transducer and how it may be used to measure displacement?
Transducer is a device which convert physical signal into electrical signal ( current/voltage/resistance). for linear measurement we can use LVDT (Linear Variable Displacement Transducer/ Linear Variable Differential Transformer). and for rotary measurement we can use RVDT (Rotary Variable Differential Transformer)
What checks should be done to an electrical measuring device before attempting to measure electrical resistance?
Some of the checks that can be done to an electrical device before checking electrical resistance include the proximity of other magnetic fields and other electrical circuits. Measure electrical resistance while at a safe distance from strong electrical circuits.
How do you convert galvanometer to ohmmeter?
Ohms are the unit of measurement for resistance, so an ohmmeter is a device that measures electrical resistance. A galvanometer measures the current flowing through the resistance, so the two are related. To convert a galvanometer into an ohmmeter, one needs an external battery.
How do you measure a thyristor?
Many users of thyristors and diodes lack the proper equipment to make measurements of semiconductor parameters. The readily available battery operated multimeter is often used to try to determine the difference between acceptable and non-acceptable devices using a resistance reading. A reading of this type can lead to incorrect conclusions. MULTIMETER MEASUREMENTS The multimeter is generally used to measure the DC resistance between anode and cathode of thyristors and diodes and also the gate to cathode on thyristors. These measurements are of the "off state" or blocking voltage of the device. The only valid readings are "open circuit" and "short circuit". The anode to cathode or gate to cathode measurement must register a short circuit in both directions ( forward and reverse polarity) for the device to be declared short and infinite resistance for an open circuit. The measurement of resistance with a multimeter is an inappropriate measurement technique for separating good devices from bad. When a resistance measurement is taken with an multimeter, the internal battery voltage is typically in the range 1.5V to 15V and the leakage current of the device at this voltage will determine the measured resistance. A semiconductor has a non-linear blocking voltage/leakage current characteristic and hence a non-linear resistance curve. The blocking voltage of a thyristor is defined as the voltage at which it reaches a specified leakage current at the defined temperature. Therefore devices can have a variety of leakage current characteristics and still be within specification. PRECAUTIONS 1. Ensure that the resistance reading is only being taken across the device and not across something in parallel with it. 2. If a capsule type device is being measured, make sure that it is under sufficient load to ensure that the internal components are pressed together and high resistance readings are avoided. SUMMARY A multimeter resistance measurement is not recommended for determining acceptable semiconductor devices. As a quick check for devices in a circuit, a multimeter will allow you to determine if a device has failed catastrophically. The device with the lowest leakage current at 3V is not necessarily the one with the lowest leakage current a high voltage
Resistance thermometer purpose of the device?
they are devices used to measure the temperature, applying the temperature to RTD element. they are sensory devices.
