Power of Components

• What should you be able to calculate by the end of this video?

  Power of electrical components
• What is power in terms of energy transfer?

  Power is the rate at which energy is transferred
• What is the unit of power?

  Watt
• How is one watt defined in terms of energy transfer?

  One watt is one joule per second
• What does a potential difference of 10 volts indicate across a resistor?

  10 joules of energy per coulomb of charge
• What does a current of 1 ampere signify?

  One coulomb of charge flowing per second
• How can you calculate the power of an electrical component?

  Power = potential difference × current
• What is the equation for calculating power?

  Power (W) = Voltage (V) × Current (A)
• Why is it important to learn the power equation?

  It is not provided in the exam
• What is the power of a resistor with a potential difference of 50 volts and a current of 0.2 amp?

  10 watts
• How do you find the potential difference across resistor A in a series circuit?

  Subtract resistor B's voltage from total voltage
• What is the total potential difference across both resistors in series if the cell is 20 volts?

  20 volts
• If resistor B has a potential difference of 15 volts, what is the potential difference across resistor A?

  5 volts
• What is the power of resistor A with a potential difference of 5 volts and a current of 0.5 amp?

  2.5 watts
• How can you calculate power if you know the current and resistance of a component?

  Power = current squared × resistance
• What is the equation for calculating power using current and resistance?

  Power = current² × resistance
• What is the power of a resistor with a current of 0.4 amp and a resistance of 50 ohms?

  8 watts
• What are the key equations for calculating power in electrical circuits?

  1. Power = Voltage × Current
  2. Power = Current² × Resistance
• What are the units for power, voltage, current, and resistance?

  • Power: Watt (W)
  • Voltage: Volt (V)
  • Current: Ampere (A)
  • Resistance: Ohm (Ω)
• What is the relationship between potential difference and current in a series circuit?

  • Potential differences are shared among components
  • Total potential difference equals the sum of individual voltages