The method and the results are on the ohm's law lab. Do the analysis yourself first, then check the answers below.
Quick answer: Ohm's law says that the current through an ohmic conductor is proportional to the potential difference across it, so V = I × R. These answers go with the grade 8 science lab on ohm's law: the graph, the calculations, the uncertainties and the conclusion explained, for all 7 analysis questions.
Model answers use the sample data. Your own readings will differ slightly, but the straight line for the resistor and the curved line for the lamp should appear in your results too.
The filament gets hotter as the current rises, so its atoms vibrate more and collide more with the moving charges, raising R from 5.0 Ω to 10 Ω. The lamp graph is a curve that bends over, unlike the straight line of the resistor.
Question 6 Uncertainty
0.01 ÷ 0.09 × 100 = 11 %. Larger currents have a smaller percentage uncertainty.
Question 7 Stronger evidence
Take more readings between 0 and 6 V, repeat each three times and average, and check the meters for zero error. Opening the switch between readings also stops heating. More points and repeats make the line more reliable.
