Page 51 - Physics - XII

Result

1. The resistance of inductor coil without iron core is _____ Ω.
2. The resistance of inductor coil with soft iron core is _____ Ω.
3. The impedance of inductor coil without iron core is _____ Ω.

4. The impedance of inductor coil with soft iron core is _____ Ω.

Precautions
1. Connect ammeter in series with the coil and voltmeter in parallel with the inductor coil.

2. Zero error of ammeter and voltmeter should be nullifi ed to zero by adjusting the pointer at zero when
no current is fl owing.
3. A.C. ammeter and voltmeter do not have uniformly spaced graduations, so reading be taken carefully.
4. Ensure that soft iron core is completely inside the inductor coil.

ACTIVITY - 2

Aim

To measure resistance, voltage (A.C./D.C.), current (A.C.) and check continuity of a given circuit using
multimeter.

Apparatus and Materials Required
A multimeter with its test leads, a resistance box, a step down transformer, a rheostat, a cell, a key,

connecting wires, and sand paper

Description of the Apparatus
A multimeter is a multi-purpose device used to measure diff erent electrical quantities like current, voltage,
and resistance in an electric circuit.
Since, it combines the functions of an ammeter, voltmeter, and ohmmeter in a single unit. Therefore, it is
also known as AVO meter.

Multimeters can be classifi ed into the following two major types depending on their construction and
working principle:
(a) Analog Multimeter: An analog multimeter displays reading through the defl ection of a pointer on
a calibrated scale.
Pointer Scale

Probs
Knob

Ports

Fig. 2.1: Analog multimeter

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