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Resistance in a bulb

Why does a hotter bulb have more resistance?

Section titled “Why does a hotter bulb have more resistance?”
  • Electrons need to travel past the metal ions in the filament.
  • Each time it collides with a metal ion, it loses energy.
  • This energy is transferred to the metal ion, making it vibrate more.
  • This makes the wire hotter.
  • This energy transfer is what we refer to as resistance.
  • As the wire gets hotter, the metal ions vibrate more.
  • This makes it harder for the electrons to pass through because there are more frequent collisions between the electrons and the vibrating metal ions.
  • This means that the resistance of the filament increases as it gets hotter, because the electrons lose more energy.