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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 checks should be done to an electrical measuring device before attempting to measure electrical resistance?
Before measuring electrical resistance, it is important to check that the device is calibrated and functioning properly, ensure the test leads are in good condition without any breaks or damage, and set the device to the appropriate resistance range for the expected measurement. Additionally, it is advisable to zero the device to account for any resistance in the test leads.
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 is the difference in an ammeter and a multimeter?
An ammeter is a device used to measure electric current in a circuit, while a multimeter is a versatile device that can measure various electrical properties like voltage, current, and resistance. A multimeter typically includes additional functions such as continuity testing, diode testing, and capacitance measurement.
How to find resistance?
To find resistance, you can use Ohm's Law, which states that resistance (R) is equal to the voltage (V) divided by the current (I). Mathematically, R = V/I. Alternatively, you can use a multimeter to directly measure the resistance of a component or circuit.
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 is the difference of volmeter and multimeter?
A voltmeter is a device used to measure voltage, while a multimeter is a versatile device that can measure voltage, current, and resistance, among other electrical properties. Essentially, a voltmeter is a specific function within a multimeter.
What is thermometer related to?
A thermometer is related to temperature measurement. It is a device used to measure the temperature of a substance or an environment.
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)
Why potentiometer is more accurate than voltmeter?
A potentiometer is able to measure very small changes in voltage by allowing the user to manually adjust the resistance until the desired voltage is reached. This control over the resistance provides a more precise and accurate measurement compared to a voltmeter, which simply displays the voltage at a fixed range without adjustment.
