Lesson Plan

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Lesson Plan
Grade: Date: 17/01/2026
Subject: Physics
Lesson Topic: recall and use P = VI, P = I 2R and P = V 2 / R
Learning Objective/s:
  • Describe the relationship between voltage, current, resistance and electrical power.
  • Derive the three power formulas (P = VI, P = I²R, P = V²/R) from basic definitions.
  • Apply the appropriate power formula to solve quantitative problems involving resistors, appliances and heating elements.
  • Analyse real‑world scenarios to select the correct formula and calculate energy consumption.
Materials Needed:
  • Projector and screen
  • PowerPoint/Google Slides with circuit diagrams
  • Worksheet with example problems and practice questions
  • Digital timer or stopwatch
  • Multimeter (demonstration only)
  • Whiteboard and markers
 Introduction:
Begin with a quick “What’s the power rating of a toaster?” hook, then ask students to recall the definitions of voltage, current and resistance. Highlight that today’s success criteria are to derive and correctly choose among the three power formulas and to solve at least three application problems accurately.
Lesson Structure:
  1. Do‑now (5'): Students write the three power formulas from memory on a sticky note; teacher collects for quick check.
  2. Mini‑lecture (10'): Derive P = VI → P = I²R → P = V²/R using work‑done and Ohm’s law, reinforcing unit consistency.
  3. Guided practice (15'): Work through Example 1‑3 together, modelling how to pick the right formula.
  4. Collaborative worksheet (15'): Pairs solve 4 practice questions, circulating to provide feedback.
  5. Check for understanding (5'): Exit quiz (3 rapid‑fire questions) projected on screen; discuss answers.
Conclusion:
Recap the three interchangeable power expressions and when each is most useful. Students complete an exit ticket stating which formula they would use for a given real‑world device and why. Assign homework: three additional problems from the textbook covering each formula.