Lesson Plan

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Lesson Plan
Grade: Date: 17/01/2026
Subject: Physics
Lesson Topic: sketch the variation of binding energy per nucleon with nucleon number
Learning Objective/s:
  • Sketch the variation of binding energy per nucleon with nucleon number.
  • Explain the physical reasons for the rise, peak, and decline of the curve.
  • Interpret how the curve predicts the suitability of fusion or fission for energy release.
  • Calculate binding energy per nucleon for given nuclei using mass‑defect data.
Materials Needed:
  • Projector or interactive whiteboard
  • Graph paper or digital plotting tool
  • Calculator (or spreadsheet)
  • Handout with sample nuclei data (mass defect, binding energy)
  • Worksheet for sketching the curve and answering questions
  • Markers and whiteboard
 Introduction:
Begin with a short video of a fusion reaction in the Sun and a fission reactor, asking students what the processes have in common. Recall their earlier work calculating mass defect and binding energy for simple nuclei. Today they will visualise how binding energy per nucleon changes with size and use the graph to explain why both processes release energy. Success will be measured by an accurate sketch and clear explanations of the curve’s features.
Lesson Structure:
  1. Do‑Now (5’) – Compute binding energy per nucleon for deuterium and helium‑4 from the handout and record results.
  2. Mini‑lecture (10’) – Review mass defect, Einstein’s relation, and introduce the Eb/A vs A curve, highlighting key features.
  3. Guided practice (12’) – Plot the provided data points on graph paper or a digital tool and connect them to form the curve.
  4. Concept discussion (8’) – In pairs, explain why the curve rises, peaks near A≈56, and declines, referencing nuclear force, surface effects, and Coulomb repulsion; teacher circulates to probe understanding.
  5. Application activity (10’) – Groups decide whether fusion or fission would release energy for given nuclei (e.g., ^2H, ^235U) using the curve and record reasoning.
  6. Check for understanding (5’) – Quick exit quiz with three short questions on curve features and energy predictions.
Conclusion:
Summarise that the peak of the binding‑energy curve marks the most stable nuclei and dictates the direction of energy‑releasing reactions. Ask students to write one sentence on the board describing how the curve guides the choice between fusion and fission as an exit ticket. Assign homework to sketch the curve from memory and annotate the three regions with their physical explanations.