Lesson Plan

• Define power as the rate at which work is done or energy is transferred.
• Distinguish between average and instantaneous power.
• Apply P = W / t and P = ΔE / t to calculate power in real‑world situations.
• Convert all quantities to SI units to obtain power in watts.
• Identify and avoid common mistakes such as unit inconsistencies.

• Projector and screen
• Power calculation worksheet
• Scientific calculators
• Physics textbook (IGCSE Chapter on Power)
• Small motor with load (50 kg mass) for demonstration
• Printed handout of formulas and unit table
• Power‑vs‑time graph poster

Begin by asking students how quickly a car can accelerate and link this to the idea of “how fast energy is used.” Review the previous lesson’s definitions of work and energy, then state that today they will learn to quantify the speed of energy transfer. Success will be measured by correctly using the power formulas in a real‑world problem.

1. Do‑now (5'): Quick quiz on work and energy concepts.
2. Mini‑lecture (10'): Define power, present P = W/t and P = ΔE/t, discuss units (W = J·s⁻¹).
3. Demonstration (8'): Show motor lifting a 50 kg mass, calculate work and time, ask students to estimate power.
4. Guided practice (12'): Students work in pairs on the provided worksheet, solving the motor example step‑by‑step.
5. Concept check (5'): Multiple‑choice questions distinguishing average vs. instantaneous power.
6. Common mistakes discussion (5'): Identify unit errors and misconceptions from the source notes.
7. Summary & exit ticket (5'): Each student writes one key takeaway and a new power problem to solve for homework.

Recap that power measures how quickly work or energy is transferred and that correct unit use is essential. Collect exit tickets to gauge understanding, and assign homework: two problems—one using P = W/t and another using P = ΔE/t—with required unit conversions.