Resistance per cm of a given wire- Physics practical

Apparatus required

• Battery Eliminator 2 or 3 Amps
• One way plug key
• Rheostat 2.3 A, 56 Ohms
• Ammeter 0 to 3 A
• Resistance coil 100 cm or any desired length
• Voltmeter 0 to 3 V
• Resistance wire (alternative)
• Connecting wire (D.C.C)

Resistance per cm of a wire-Circuit Diagram

Resistance  per cm of a wire:Experimental setup

Resistance per cm of a wire-Procedure

• Connect the ammeter in series with the circuit wire and the voltmeter in parallel with the wire.
• Note the zero error of the meters.
• Calculate the least count of the meters.
• Switch on the circuit.
• Set the rheostat to a particular position and record the readings of the ammeter and voltmeter.
• Repeat steps 5 and 6 for different settings of the rheostat.
• Tabulate the readings.
• Calculate the resistance of the wire using the formula R=V/I
• Resistance per cm is calculated from the above value.

Least count of an ammeter

Least count of a voltmeter

Resistance per cm of a wire:Tabular Column & Observation

Mapping potential-Graphing voltage against current

Unveiling wire resistance-A practical exploration by experimental and graphical method

RESULT

The length of the given wire is 100 cm

The resistance per cm of the given wire is 0.03 Ohms

LINKS TO OTHER EXPERIMENTS:

Comparison of emf of two cells using potentiometer

Internal resistance of a cell using potentiometer

Meter bridge experiment

Electricity experiments grade 12