Lesson Plan

• Define the moment (torque) of a force and express it mathematically.
• Explain how force magnitude, perpendicular distance, and angle affect the turning effect.
• Identify and analyse everyday examples that illustrate moments.
• Apply the principle of moments to determine rotational equilibrium in simple systems.
• Solve basic torque calculations using τ = F d sinθ.

• Projector or interactive whiteboard
• Slide deck with lever and torque diagrams
• Simple tools: door handle, wrench, seesaw or lever kit
• Worksheets with torque problems
• Ruler or measuring tape
• Calculator for each student

Begin with a quick demonstration: ask a student to try opening a heavy door by pushing near the hinges versus at the handle. Discuss how the same force can feel different, linking to prior knowledge of force and motion. Explain that today’s success criteria are to describe the moment of a force, predict its turning effect, and use everyday examples to illustrate the concept.

1. Do‑Now (5’) – Students answer: “If you push a door at the knob versus the edge, which requires less effort and why?” Collect responses.
2. Mini‑lecture (10’) – Present definition, formula τ = F d sinθ, units, and sign convention with slides and a lever diagram.
3. Guided practice (12’) – Work through the sample table, calculate moments for three cases, students complete worksheet.
4. Demonstration stations (15’) – Small groups rotate through: (a) opening a door, (b) using a wrench on a bolt, (c) balancing a seesaw model, recording forces, distances, and predicted moments.
5. Concept check (8’) – Quick quiz on the principle of moments and sign conventions using clickers or show of hands.
6. Summary discussion (5’) – Review key points and connect to real‑world tools.

Total ≈ 55 minutes.

Recap that the moment quantifies a force’s turning ability and depends on magnitude, distance, and angle, and that balancing moments yields rotational equilibrium. For the exit ticket, students write one everyday example not covered today and state the torque formula they would use. Homework: complete the worksheet with three additional torque calculations and a short paragraph explaining how a longer lever makes work easier.