Casio fx-7400G PLUS Booklet page 29

Analysis – Step 3
The shapes of the graphs produced when resistors are used differ from the graph produced by
the light bulb. In the case of resistors, the graph is linear and passes through the origin, but the
light bulb resistance graph is different. What does this tell you about the resistance of a light
bulb? Write down your thoughts.
The resistance of the light bulb increases as the voltage applied rises.
• What causes the phenomena we observed in Analysis - Step 3?
As voltage increases, more current flows through the filament, causing it to become
hotter.
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EE-2 Ohm's Law