Lesson Plan

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Lesson Plan
Grade: Date: 01/12/2025
Subject: Physics
Lesson Topic: explain the use of a single diode for the half-wave rectification of an alternating current
Learning Objective/s:
  • Describe the operation of a diode and its role in half‑wave rectification.
  • Calculate the peak, average, and RMS output voltages of a half‑wave rectifier.
  • Explain the effect of ripple and how a smoothing capacitor reduces it.
  • Analyse the advantages and limitations of a single‑diode rectifier.
Materials Needed:
  • Projector or interactive whiteboard
  • Computer with circuit simulation software (e.g., Falstad or LTspice)
  • Breadboard, 1N4007 diode, load resistor, AC power source
  • Oscilloscope or voltage probe for demonstration
  • Handout with circuit diagram and key formulas
  • Worksheet for calculations and reflection
 Introduction:
Begin with a quick demonstration comparing a battery‑powered flashlight to an AC source to spark curiosity. Recall that diodes permit current flow in only one direction. Today we will explore how a single diode can convert an AC signal into a pulsating DC and predict the resulting voltage characteristics.
Lesson Structure:
  1. Do‑now (5'): Students answer a short question on diode polarity on a worksheet.
  2. Mini‑lecture (10'): Explain forward/reverse bias and the half‑wave principle using an animation.
  3. Guided simulation (12'): Build the half‑wave rectifier in simulation software and observe input/output waveforms.
  4. Hands‑on build (15'): Assemble the circuit on a breadboard, measure waveforms with an oscilloscope, record peak, average, and RMS values.
  5. Ripple discussion (8'): Introduce a smoothing capacitor, derive the ripple‑voltage formula, and calculate expected ripple.
  6. Exit ticket quiz (5'): One calculation and one conceptual question to check understanding.
Conclusion:
Recap that a single diode clips the negative half‑cycle, producing a pulsating DC with characteristic ripple. Students complete an exit ticket calculating the average output voltage for a given peak value. For homework, they will design a simple RC filter, predict the ripple reduction, and prepare a brief explanation of its operation.