A moving iron voltmeter is an instrument used to measure the voltage of an electrical circuit. It works by using a piece of iron that moves in response to the magnetic field created by the current in the circuit. The greater the voltage, the stronger the magnetic field and the more the iron moves.
The percentage error for a moving iron voltmeter is calculated by taking the absolute value of the difference between the measured value and the true value, dividing it by the true value, and then multiplying by 100. The formula is: (|measured value - true value| / true value) x 100.
The true value in the percentage error calculation for a moving iron voltmeter is the actual voltage of the circuit being measured. This can be determined through calibration or by using a known voltage source.
The acceptable percentage error for a moving iron voltmeter depends on the application and the level of accuracy required. Generally, a percentage error of less than 5% is considered acceptable, but for more precise measurements, a lower percentage error may be necessary.
The percentage error for a moving iron voltmeter can be reduced by using a more accurate voltmeter, ensuring proper calibration, and minimizing external influences such as temperature and electromagnetic interference. It is also important to take multiple measurements and calculate an average to reduce random errors.