Final answer:
To test an inductor with an ohmmeter, disconnect it from any circuit and connect the ohmmeter's leads to it. A functional inductor will show a small resistance. An ohmmeter cannot measure inductance; it requires AC for that.
Step-by-step explanation:
Testing an Inductor with an Ohmmeter
To test an inductor using an ohmmeter, start by ensuring the inductor to be tested is disconnected from any circuitry. Attach the ohmmeter's leads to the inductor terminals, and observe the reading. A functioning inductor should show a small resistance value, indicating the resistance of the wire it is made from. If the ohmmeter indicates an open circuit (infinity resistance), this suggests that the inductor's coil is broken. Conversely, if the ohmmeter reads zero resistance, the inductor may be short-circuited. However, an ohmmeter alone cannot measure inductance since it requires alternating current to produce a varying magnetic field.
For calculating the inductance of an inductor, the following steps can be performed:
(1) Assume a current I is flowing through the inductor;
(2) Determine the magnetic field B;
(3) Obtain the magnetic flux Θm; and
(4) With the flux known, use the equation L = NΘm/I to find the self-inductance L.
To measure the inductive reactance, one would use the expression X₁ = 2πfL at different frequencies, and then apply Ohm's law I = V/X₁ to find the current at each frequency if the voltage is known.