PEKA 1

ANALYSING THE RELATIONSHIP BETWEEN ELECTRIC CUREEN AND

POTENTIAL DIFFERENCE

AIM

• To find the relationship between current and potential difference for an ohmic conductor.

INFERENCE

• The potential difference , V , across an ohmic conductor is influenced by the current , I , flowing through it.

Hypothesis

• The potential difference , V , across an ohmic conductor is directly proportional to the current , I , flowing through it.

Variables

• Manipulated : Current , I

• Responding : Potential difference , V

• Fixed : Physical conditions of the ohmic wire

Operational Definition

• Current is the reading of the ammeter. Potential difference is the reading of the voltmeter.

Diagram

• Draw it .. Check on the board!! >>>> Leave some space… for that

Apparatus

• Dry cells holder , ammeter (0-1 A) , voltmeter (0-5 V) , rheostat , connecting wires and switch.

Materials

• 4 pieces of 1.5 V dry cell , 10cm of constantan wire (s.w.g. 22).

Method

• 1. The apparatus was set up as shown in the figure.

• 2. The switch was turned on and the rheostat was adjusted until the ammeter read the current , I = 0.3 A .

• 3. The reading of the potential difference , V , was taken from the voltmeter. The reading were recorded.

• 4. Steps 2 and 3 were repeated for I = 0.4A, 0.5A , 0.6A , 0.7A, and 0.8A.

• 5. A graph of V against I was plotted.

Results

• 1. Write the values of I and V obtained from the experiment in the form of a table.

• >>>>>>>>>>>>>>>>>>

• 2. Plot a graph of V against I based on the table above.

• ( Draw ur own graph )

Conclusion

• The potential difference , V , across an ohmic conductor is directly proportional to the current , I , flowing through it.

Precautions

• 1. The ammeter and voltmeter was checked for zero error and adjusted accordingly before carrying out the experiment.

• 2. The readings of ammeter and voltmeter were carried out with the eye directly above the indicator to prevent parallax error.

Precautions

• 1. The ammeter and voltmeter was checked for zero error and adjusted accordingly before carrying out the experiment.

• 2. The readings of ammeter and voltmeter were carried out with the eye directly above the indicator to prevent parallax error.

-The End -

• By Ada …. ^-^