Practical Report:
Experiment: Ohmic Resistance and Ohm’s Law
Patrick Doan
Mr Sadowsky
11 PHYS 71
12/9/08
Table of contents
1.0 Aim 1
2.0 Hypothesis 1
3.0 Materials 1
4.0 Method 2
5.0 Results 3 - 5.1 Qualitative Observations 3 - 5.2 Data 3-4
6.0 Discussion 5
7.0 Conclusion 6
8.0 Bibliography 7
9.0 Acknowledgements 7 1.0 Aim:
To find out how current, voltage and resistance in a circuit are related, also to discover the relationship known as ‘Ohm’s Law’.
2.0 Hypothesis:
In this experiment, conductors are used. Conductors which obey Ohm’s Law are called Ohmic conductors. Thus, for an ohmic conductor, a graph of V (Voltage) verses I (Current) is a straight line passing through the origin. A conductor that does not obey Ohm’s Law is called a non-ohmic conductor.
Ohm’s Law:
3.0 Materials:
• Power Pack 12V
• Voltmeter
• Light bulb
• 9 Alligator clips
• Ammeter
• Test tube
• Switch
• Multimeter
Patrick Doan 1
4.0 Method:
1. Collect all equipment and make sure the surface is clean and not wet
2. Wrap the nichrome wire around the test-tube to form a coil
3. Use the multimeter to measure the resistance of the light bulb
4. Connect the power pack to the power point but do not switch it on
5. Set up a series circuit with the ammeter, switch, nichrome wire resistor (Figure 1), light bulb (Figure 2) connected in a series and connect the voltmeter in parallel with the nichrome wire or light bulb resistor. Use two alligator clips as a switch
6. To begin, turn the power source to the lowest setting. Switch on the power and record the reading on the voltmeter and the ammeter
7. Switch the circuit off and allow for the nichrome wire or light bulb to cool
8. Increase the power supply setting by one and record the result from the ammeter and voltmeter
9. Continue to increase the power supply in steps of one until power supply is at
Bibliography: Microsoft Encarta Encyclopedia Standard, 2005, CD ROM, Microsoft Corporation, U.S.A 9.0 Acknowledgements