Lesson Plan

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Lesson Plan
Grade: Date: 25/02/2026
Subject: Physics
Lesson Topic: Apply the principle of moments to other situations, including those with more than one force each side of the pivot
Learning Objective/s:
  • Describe the concept of a moment (torque) and calculate it using M = F × d.
  • Distinguish clockwise and counter‑clockwise moments and apply the correct sign convention.
  • Apply the principle of moments to systems that have multiple forces on each side of a pivot.
  • Solve for unknown forces or distances by setting ΣM_CW = ΣM_CCW.
  • Check solutions for correct units and physical plausibility.
Materials Needed:
  • Projector or interactive whiteboard
  • Printed worksheet with lever diagrams
  • Set of small masses and a metre ruler for a hands‑on demo
  • Calculators (or calculator apps)
  • Whiteboard and markers
  • Student notebooks
 Introduction:
Begin with a quick demonstration of a seesaw tipping when unequal weights are placed on either side, prompting students to predict the outcome. Review the definition of a moment and the clockwise/counter‑clockwise convention from previous lessons. Explain that today’s success criteria are to correctly set up and solve a moment equation for a lever with several forces on each side.
Lesson Structure:
  1. Do‑Now (5'): Short question on identifying clockwise vs. counter‑clockwise moments from a given diagram.
  2. Mini‑lecture (10'): Review M = F d, sign convention, and the principle ΣM_CW = ΣM_CCW.
  3. Guided practice (15'): Teacher models the step‑by‑step procedure on the example beam, projecting calculations.
  4. Collaborative activity (15'): In pairs, students create their own lever diagram with at least two forces per side, calculate moments, and solve for an unknown.
  5. Check for understanding (5'): Quick quiz (clickers or show‑of‑hands) on common mistakes.
  6. Summary & exit ticket (5'): Students write one correct moment equation and one common error to avoid on a sticky note.
Conclusion:
Recap that balancing a lever requires summing clockwise and counter‑clockwise moments and ensuring they are equal. Students submit an exit ticket stating the equation they used and the answer they found. For homework, assign two additional problems involving off‑centre pivots from the textbook.