Filament bulb experiment
Evaluation
I think my evidence is reliable because the anomalies in my first results were the same as the ones in my second results. The graph made a straight line with a gradient that gets deeper that is what I predicted. To improve my experiment to make it even more reliable I could use a more accurate ammeter and a larger range of results as well as more checks. The ammeter I use could be more than two decimal places, and I could get a lot of results and put them on one graph to make my results are reliable and I have a good accurate graph. Analysis
When the bulbs received more current the molecules in the bulb vibrated fast and the bulb became warmer as the resistance increased.
As the voltage increased the current and resistance did also.
The resistance of the 6V bulb increased as the current and voltage did. However, in the pure resistor trial experiment the resistance stayed around the same as the current and voltage increased.
The difference between the bulbs and trial experiment graphs are that the bulb graph was a straight line with an increasingly deeper gradient and the other was directly proportional to the voltage. The reason the bulb graph curved is because as the bulb became hotter the molecules vibrated more, so the resistance increased. I have circled the anomalous result on the graph and found that the anomalous results in my first experiment were the same as in my check experiment. This shows that my results are reliable.
The trial experiment graph obeys Ohm's Law because it is directly proportional but my bulb experiment doesn't.
My conclusion supports my initial prediction as the resistance did increase and the results made a graph with a positive straight line
with a gradient which less steep.
I think my evidence is reliable because the anomalies in my first results were the same as the ones in my second results. The graph made a straight line with a gradient that gets deeper that is what I predicted. To improve my experiment to make it even more reliable I could use a more accurate ammeter and a larger range of results as well as more checks. The ammeter I use could be more than two decimal places, and I could get a lot of results and put them on one graph to make my results are reliable and I have a good accurate graph. Analysis
When the bulbs received more current the molecules in the bulb vibrated fast and the bulb became warmer as the resistance increased.
As the voltage increased the current and resistance did also.
The resistance of the 6V bulb increased as the current and voltage did. However, in the pure resistor trial experiment the resistance stayed around the same as the current and voltage increased.
The difference between the bulbs and trial experiment graphs are that the bulb graph was a straight line with an increasingly deeper gradient and the other was directly proportional to the voltage. The reason the bulb graph curved is because as the bulb became hotter the molecules vibrated more, so the resistance increased. I have circled the anomalous result on the graph and found that the anomalous results in my first experiment were the same as in my check experiment. This shows that my results are reliable.
The trial experiment graph obeys Ohm's Law because it is directly proportional but my bulb experiment doesn't.
My conclusion supports my initial prediction as the resistance did increase and the results made a graph with a positive straight line
with a gradient which less steep.