Suggested Improvements:
The investigation could have yielded more accurate results if the following modifications were made in future:
1. To deal with the first problem, a power source that allows the voltage to be set to a more accurate value might have been used. It would have been possible to come nearer to the wanted voltage value if the tools allowed doing so.
2. To deal with the second problem, a voltmeter and ammeter that allow to be connected together (or to a computer) might have been used. That way it would be possible to record the current at the same instant that the correct voltage value was set. The human error would be eliminated because the data would be displayed graphically on the computer and then easily processed.
Conclusion:
The aim of the experiment was to investigate whether resistance can be determined accurately by measuring voltage and current in an electric circuit.
8
From the graphs it can be seen that voltage is proportional to current in an electric circuit where resistance is the coefficient of proportionality.
The gradient of the straight line was then used to calculate the value of the resistance of the light bulb and resistor.