Ohmmeter

An ohmmeter is a machine that measures electrical resistance in the flow of an electric current. There are two kinds of Ohmmeter. The first is the Microohmmeters which is used for low resistance measurements. The second is the Megaohmmeters which measures large resistance.

The first ohmmeters had a small battery to apply voltage to a resistance. The measurement of the resistance was by using a galvanometer. The scale was marked in ohms. Nowadays, the ohmmeter has an electronic circuit that sends a current (I) through the resistance, and another circuit measures voltage across the resistance.

An Ohmmeter

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