Title?
How current varies with voltage in a resistor.
Aim?
To investigate how current changes with voltage in a resistor.
Data collection and Handling?
I set up the circuit with a variable power supply, a fixed resistor, an ammeter in series to measure current, and a voltmeter in parallel to measure voltage. The voltage was increased in steps, and the corresponding current and voltage were recorded.
Drawing of circuit*
Results: Experiment graph + table (with avg.)
Data from Internet source: printed out graph*
I got this graph from the internet the URL: printed out URL*
Underlying Physics?
This experiment tests Ohm’s Law.
Ohm’s Law states that current is directly proportional to voltage if temperature is constant.
Equation: V(voltage)=I(current )x R(resistor) or I=V/R
In this experiment, the resistor stays constant, voltage is changed, and current is measured.
Ohm’s Law predicts a straight-line graph of current and voltage through the origin.
Analysis?
My results show that as voltage increased, current also increased. This matches what I expected from Ohm’s Law, which states that current is directly proportional to voltage. The graph is a straight line through the origin, which supports this. This means my results agree with the theory and the values from my internet source.
Conclusion?
My aim was to investigate how voltage affects current in a resistor. The results show that when voltage increases, current also increases in a proportional way. This supports Ohm’s Law and shows that the resistor follows the expected relationship.
Evaluation?
One problem in my experiment was that the resistor could heat up as current increased. This could change the resistance and affect my results, making them less accurate.
To improve this, I could let the resistor cool down between readings. I could also repeat each reading and take an average. Using more precise digital equipment would also improve accuracy.
