Resistors

• What is a resistor?

  A resistor is a component that adds resistance to a circuit.
• What is the symbol for a resistor?

  The symbol for a resistor is a zigzag line.
• What does the current potential difference graph for an ohmic conductor represent?

  It shows that current is directly proportional to potential difference.
• What happens to electrical energy as electrons move through a conductor?

  Electrical energy is transferred into other forms of energy, such as thermal energy.
• How is resistance calculated?

  Resistance is calculated by dividing potential difference by current.
• What is the unit of resistance?

  The unit of resistance is the ohm.
• Why might resistance be considered useful in a circuit?

  Resistance can be used to control the brightness of a lamp or other components.
• If a lamp is too bright, how can you reduce its brightness?

  You can add a resistor in series with the lamp.
• What is the resistance of a resistor if the potential difference is $10 \text{ volts}$ and the current is $0.1 \text{ amp}$?


  The resistance is $100 \text{ ohms}$.
• What does a straight line passing through zero on a current-potential difference graph indicate?

  It indicates that the current is directly proportional to the potential difference.
• What happens to the current when the potential difference across a resistor is increased?

  The current increases as the potential difference increases.
• Under what condition does the resistance of an ohmic conductor remain constant?

  The resistance remains constant if the temperature is constant.
• What is an ohmic conductor?

  An ohmic conductor is a type of resistor where resistance remains constant.
• Where can you find questions on resistors for practice?

  You can find questions on resistors in the vision workbook.