Question

Measure the resistance and impedance of an inductor

Answer 1

To Measure the Resistance and Impedance of an Inductor With or Without Iron Core

Aim

To measure the resistance and impedance of an inductor with or without iron core.

Apparatus and material

Apparatus. A battery, a high resistance rheostat, D.C. ammeter, D.C. voltmeter, one way key, variable A.C. source (variac), A.C. ammeter, A.C. voltmeter, connecting wires.

Material. A high resistance and large number of turns coil wrapped on a hollow cylindrical asbestos core, a soft iron rod fitting into the asbestos core.

Procedure

Measurement of resistance:

Make circuit as shown in circuit diagram (figure (a) an

d figure (6)) and determine resistance applying Ohm’s law.

Measurement of impedance without iron core:

Make circuit as shown in circuit diagram (figure (c) and figure (d)). The variac (variable output A.C. source) is connected to A.C. Mains, A.C. ammeter and A.C. voltmeter are used for measuring A.C. current and voltage.

The circuit will obey Ohm’s law. The ratio of the voltmeter reading to the corresponding ammeter reading will give the impedance of the inductor (without iron core).

Measurement of impedance with iron core:

Now insert the iron core inside the hollow cylindrical asbestos core of the inductor. Repeat the above steps to find the impedance of the inductor with iron core.

Answer 2

To Measure the Resistance and Impedance of an Inductor With or Without Iron Core

Explanation:

Apparatus required:

A battery, High resistance rheostat , D.C and A.C ammeter and voltmeter , one way key, A.C source ,inductor coil , iron core and connecting wires.

Without iron Core:

• To measure the impedance and resistance of an inductor an circuit is made.
• The variable output source of the circuit is connected to A.C mains A.C ammeter and A.C voltmeter for measuring A.C current and voltage.
• The circuit will obey ohm's law.

With iron core:

• Insert the iron core inside the hollow core of the inductor and then connect it to the A.C mains, A.C ammeter and A.C voltmeter for measuring current and voltage.
• Repeat the above steps to find the impedance of the inductor with iron core.