Lesson Plan

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Lesson Plan
Grade: Date: 17/01/2026
Subject: Physics
Lesson Topic: define resistance
Learning Objective/s:
  • Describe the concept of electrical resistance and its relationship to voltage and current.
  • Explain how resistivity, length, and cross‑sectional area determine a conductor's resistance.
  • Apply Ohm’s law and the resistivity formula to calculate resistance of a uniform wire.
  • Analyse how changes in length or area affect resistance in practical scenarios.
Materials Needed:
  • Projector or interactive whiteboard
  • Slides with definitions, formulas, and diagram
  • Calculator or simulation app for resistance calculations
  • Sample wires of different lengths and gauges
  • Worksheet with practice problems
  • Whiteboard and markers
 Introduction:
Begin with a quick demonstration: connect a simple circuit and ask students what might impede the flow of electricity. Recall prior learning of voltage, current, and Ohm’s law, linking it to today’s focus on resistance. State that by the end of the lesson they will be able to define resistance, explain the factors that influence it, and calculate resistance for a given conductor.
Lesson Structure:
  1. Do‑now (5'): Students answer a short quiz on voltage and current displayed on the board.
  2. Teacher input (10'): Present definition of resistance and Ohm’s law using slides and a diagram of a uniform conductor.
  3. Guided practice (12'): Work through the copper‑wire example together, highlighting the use of R = ρ L⁄A.
  4. Collaborative activity (15'): In small groups, students use sample wires and calculators to predict how changing length or area alters resistance, then test with a simulation.
  5. Check for understanding (8'): Quick exit ticket where each student writes the resistance formula and one influencing factor; teacher reviews responses.
Conclusion:
Summarise that resistance quantifies how a material opposes current and is governed by resistivity, length, and cross‑sectional area. Ask a few students to share their exit‑ticket answers to reinforce the key relationships. Assign a homework task to calculate resistance for two different wires using given dimensions.