When measuring the internal resistance of ammeter, just regard ammeter as a resistance.

Any method of measuring resistance can be used to measure the internal resistance of ammeter. The difference is to ensure that the current through the ammeter does not exceed Ig, so as not to damage the ammeter.

Of course, it can be measured with a bridge. Use a galvanometer as one arm of the bridge. How to ensure that the current through the ammeter does not exceed Ig? Just add a voltage regulating circuit to the power supply to control the voltage of the power supply.

Extended data:

The resistance value of resistance elements is generally related to temperature, material, length and cross-sectional area. The physical quantity to measure the influence of temperature on resistance is temperature coefficient, which is defined as the percentage of resistance change when the temperature rises by 65438 0℃. The main physical feature of resistance is that the converted energy is thermal energy, or it can be said that it is an energy-consuming element, through which current generates internal energy. Resistors usually act as voltage dividers and shunts in circuits. For signals, both AC and DC signals can pass through resistors.

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