RP: factors that affect resistance

• What is the main topic of the practical experiment described in the study material?

  Factors that affect resistance
• What are the two types of electrical current mentioned?

  Direct and alternating current
• What is the unit of resistance?

  Ohms
• What does potential difference measure in a circuit?

  The energy given to the charge carriers
• What is the formula to calculate resistance?

  R = V/I
• If the potential difference is 10 V and the current is 2 A, what is the resistance?

  $R =$$\frac{10 \text{ V}}{2 \text{ A}} =$$5 \Omega$
• What is the aim of the experiment described in the study material?

  • To investigate how changing the length of the wire affects its resistance.
• What apparatus is used to measure electric current?

  Ammeter
• What apparatus is used to measure potential difference?

  Voltmeter
• How do you calculate resistance using voltage and current readings?

  By using the formula $R =$$\frac{V}{I}$
• What is the relationship between the length of the wire and its resistance based on the experiment's results?

  • Resistance increases as the length of the wire increases.
  • Resistance is directly proportional to length.
• What is the consequence of heating the resistance wire during the experiment?

  Burns to the skin
• What control measures should be taken to avoid burns from the resistance wire?

  Do not touch the wire while the circuit is connected and allow it to cool.
• What does the graph of resistance against length indicate?

  It shows that resistance is directly proportional to length.
• What is the potential difference measured in?

  Volts (V)
• What is the definition of electrical current?

  Moving electric charges, such as electrons moving through a metal wire.
• What is the purpose of using crocodile clips in the experiment?

  To connect the resistance wire at specified lengths.
• If the resistance of a wire is found to be 3 Ω at a length of 40 cm, what would you expect the resistance to be at 80 cm?

  Approximately 6 Ω, since resistance is directly proportional to length.