resistance of a filament lamp

• What is the relationship between current and potential difference in a resistor?

  Current is directly proportional to potential difference
• What symbol represents a resistor in a circuit?

  Resistor symbol
• What type of conductors are resistors that follow Ohm's law?

  Ohmic conductors
• Under what condition does the resistance of a resistor remain constant?

  If the temperature does not change
• What happens to the resistance of a filament lamp as it gets hotter?

  The resistance increases
• Why does the current through a filament lamp not remain directly proportional to the potential difference?

  Because the filament gets hot, increasing resistance
• How does the vibration of atoms in the filament affect electron flow?

  More collisions occur, requiring more energy
• What is the shape of the current potential difference graph for a filament lamp?

  Non-linear, not directly proportional
• What are the key characteristics of a filament lamp?

  • Contains a fine wire filament
  • Filament glows when heated by current
  • Not energy efficient
  • Resistance increases with temperature
• What happens to the current as the potential difference increases in a filament lamp?

  The current increases less than proportionally
• How does the behavior of a filament lamp differ from that of an ohmic conductor?

  A filament lamp's resistance increases with temperature