Work, Energy, and Power - Definitions and Units

Grade 10 · Physics

Semester 1 | Period 3 | Week 13

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Subject: Physics

Semester: 1

Period: 3

Week: 13

School Name:

Teacher’s Name:

Subject: Physics

Grade Level: Grade 10

Week & Period: Week 13, Period III

Date:

Sub-topic: Work, Energy, and Power – Definitions and Units

Learning Objectives:
By the end of the lesson, learners should be able to:

  1. Define work, energy, and power.
  2. State the S.I units of each quantity.
  3. Solve basic problems involving work, energy, and power.
  4. Differentiate between types of energy.

Instructional Materials:

  • Chart with formulae
  • Pulley and load system
  • Stopwatches
  • Masses and inclined planes
  • Meter rule and Newton spring balance

Anticipation (Warm-Up):
Ask learners:

  • “Have you ever pushed a wheelbarrow or lifted a bucket of water?”
  • “How would you describe the effort you put into it?”

Building Knowledge:

  1. Work:
    • Work is done when a force causes displacement:
      (W = F × d)
    • Unit: Joule (J)
  2. Energy:
    • Capacity to do work
    • Forms include kinetic, potential, chemical, thermal, etc.
    • Unit: Joule (J)
  3. Power:
    • Rate of doing work:
    • Unit: Watt (W)

Solved Example 1:
A force of 10 N moves a load 5 m.
Work done = 10 × 5 = 50 J

Solved Example 2:
Work done = 120 J in 10 s
Power = 120 ÷ 10 = 12 W

Activities:

  • Lift weights over distances and record work done
  • Use stopwatches to calculate time and determine power
  • Compare heavier vs. lighter objects in doing work

Assessment:
Oral:

  1. What is the S.I unit of energy?
  2. Define power.

Written:

  1. A force of 15 N moves an object 8 m. Calculate the work done.
  2. Calculate power when 600 J of work is done in 20 seconds.

Homework:

  1. Differentiate between +work and energy with examples.
  2. List five forms of energy and give an example of each.

Expanded Notes:

  • Work is scalar and only done if displacement occurs
  • Energy is stored capacity; power tells how fast it is used
  • Use analogies like running vs. walking with the same effort

Differentiation:

  • Visuals of charts and real-life examples
  • Group activities to promote peer learning
  • Break equations down into steps for struggling learners

Teacher’s Reflection:

  • Were learners able to relate the concepts to real-life experiences?
  • Could they apply formulas correctly?
  • Who needs help differentiating energy types?