Resistors in Series and Parallel

• What is the equation for resistance?

  Resistance = potential difference / current
• How do you calculate the current in a circuit with a 5 volts potential difference and a 100 ohm resistor?

  Current = 5 volts / 100 ohms
• What is the current flowing in the circuit with a 5 volts potential difference and a 100 ohm resistor?

  0.05 amp
• What happens to the total resistance when resistors are in series?

  They add together
• What is the total resistance of a 100 ohm resistor and a 50 ohm resistor in series?

  150 ohms
• Why do resistors add in series?

  Current passes through each resistor sequentially
• What is equivalent resistance?

  Replacement of multiple resistors with one
• How do you calculate the current in a circuit with a potential difference of 20 volts and a total resistance of 150 ohms?

  Current = 20 volts / 150 ohms
• What is the current in the circuit with a potential difference of 20 volts and a total resistance of 150 ohms?

  0.13 amp
• What is the total resistance of a 20 ohm, 15 ohm, and 10 ohm resistor in series?

  45 ohms
• How do you calculate the current with a potential difference of 10 volts and a total resistance of 45 ohms?

  Current = 10 volts / 45 ohms
• What is the current when the potential difference is 10 volts and the total resistance is 45 ohms?

  0.22 amp
• How do you calculate the potential difference across resistors?

  Potential difference = resistance × current
• What is the total resistance of a 200 ohm and a 75 ohm resistor in series?

  275 ohms
• How do you calculate the potential difference with a total resistance of 275 ohms and a current of 0.5 amp?

  Potential difference = 275 ohms × 0.5 amp
• What is the potential difference when the total resistance is 275 ohms and the current is 0.5 amp?

  137.5 volts
• What is a key fact about the total resistance of resistors in parallel?

  It is less than the smallest individual resistor
• Why does total resistance decrease in parallel circuits?

  More pathways for current to flow
• What is the total resistance of a 150 ohm and a 200 ohm resistor in parallel?

  Less than 150 ohms
• What happens to current in a parallel circuit compared to a series circuit?

  More total current flows in parallel
• How does the equation relate current and potential difference in a circuit?

  Increased current means decreased resistance
• What are the steps to calculate total resistance in series circuits?

  • Add the resistance values together
  • Use the formula: Total Resistance = R1 + R2 + ...
• What are the steps to calculate current in a circuit?

  • Use the formula: Current = Potential Difference / Resistance
  • Substitute the values into the equation
• What are the steps to calculate potential difference in a circuit?

  • Use the formula: Potential Difference = Resistance × Current
  • Substitute the values into the equation
• What are the characteristics of resistors in parallel?

  • Total resistance is less than the smallest resistor
  • More pathways for current flow