2.3.1 Alternating Current (AC) and Direct Current (DC)

• What is alternating current (AC)?

  Current that reverses direction
• Direct current (DC) flows in only one
• Match the feature with the correct type of current:

  Current reverses direction ↔️ AC

  Current flows in one direction ↔️ DC
• The voltage in DC remains constant
• What are common uses of DC?

  Batteries, small electronics
• Order the features of AC and DC based on their differences:

  1️⃣ Current Direction: Periodically reverses (AC) vs. Flows in one direction (DC)

  2️⃣ Frequency: 50 Hz in the UK (AC) vs. 0 Hz (DC)

  3️⃣ Voltage: Varies sinusoidally (AC) vs. Constant (DC)
• Match the type of current with its voltage behavior:

  AC ↔️ Varies sinusoidally

  DC ↔️ Constant
• What is the frequency of DC?

  0 Hz
• The frequency of AC in the UK is 50 Hz.
• The voltage in AC is constant.

  False
• What are common uses of AC?

  Household power, large appliances
• Match the feature with the correct type of current:

  Periodically reverses ↔️ AC

  Flows in one direction ↔️ DC
• DC has a frequency of 0 Hz.
• The voltage in DC varies sinusoidally.

  False
• What is the voltage behavior of AC?

  Varies sinusoidally
• The current direction in AC periodically reverses.
• What is the frequency of DC in the UK?

  0 Hz
• What is the voltage behavior of DC?

  Constant
• The frequency of AC in the UK is 50 Hz.
• What are common uses of AC?

  Household power, large appliances
• DC flows in only one direction.
• Match the feature with the correct type of current:

  Current Direction: Periodically reverses ↔️ AC

  Current Direction: Flows in one direction ↔️ DC
• What is the frequency of DC?

  0 Hz
• The voltage in AC varies sinusoidally.
• What are common uses of DC?

  Batteries, small electronics
• DC has a frequency of 0 Hz.
• The voltage in DC remains constant.
• What is the voltage behavior of AC?

  Varies sinusoidally
• The current direction in AC periodically reverses.
• The frequency of AC in the UK is 50 Hz.
• What are common uses of DC?

  Batteries, small electronics
• Match the waveform with its description:

  AC Waveform ↔️ Sinusoidal, reverses periodically

  DC Waveform ↔️ Constant voltage, flows one direction
• AC periodically reverses direction, while DC flows in only one direction.
• In the UK, AC has a frequency of 50 Hz.
• What is the frequency of DC in Hz?

  0 Hz
• AC waveforms are sinusoidal and periodically reverse direction.
• The voltage of AC in the UK is represented as V(t) = V_{0} \sin(2\pi ft)</latex>, where f is the frequency.
• What type of voltage does DC maintain?

  Constant
• AC waveforms in the UK have a frequency of 50 Hz and are sinusoidal.
• DC maintains a constant voltage and has a frequency of 0 Hz.