Measuring Work

Grade 6 · General Science

Semester 2 | Period 5 | Week 26

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Subject: General Science

Semester: 2

Period: 5

Week: 26

School Name:
Teacher’s Name:
Subject: General science
Grade Level: Grade 6
Date: Week 26
Lesson Duration: 45 minutes
Week & Period: Week 26, Period 5
Topic: Measuring Work
Sub-topic: Concept of work in science, units of work, lifting, pushing, pulling, difference between work in daily use vs. scientific meaning
Learning Objectives
By the end of the lesson, students should be able to define work scientifically, calculate work using force and distance, and distinguish between everyday and scientific meanings of work.

Previous Knowledge
Students already know that work involves effort and movement.

Instructional Materials
Spring scales, weights, measuring tapes, chart paper, markers, simple activity setups for lifting and pushing objects.

Lesson Development – ABC Model
A – Anticipation (Warm-up / Starter)
Time: 5–10 minutes
Ask learners to discuss examples of work at home or school and what they think makes work “hard.”

B – Building Knowledge (Main Lesson Body)

Time: 25–30 minutes

Learners’ Activities (Expanded):

  • Students use spring balances/scales to measure the force needed to lift or drag small objects (e.g., books, a block of wood, a filled bottle).
  • In pairs, learners record the force (in Newtons) and the distance moved (in meters).
  • They use the formula Work = Force × Distance to calculate the amount of work done.
  • Teacher demonstrates the formula on the board with step-by-step calculations.
  • Class compares two situations:
  1. Lifting a stone (force applied and object moves).
  2. Pushing hard on a wall (force applied but no movement).
    Learners discuss why only the first counts as scientific “work.”
  • Students discuss why in everyday language, we may say “I worked hard today” even if no physical movement happened, and compare it with the scientific definition.

Assessment Checks:

  1. Teacher asks learners to state the formula for work.
  2. Learners solve a simple problem: If a force of 10 N moves a box 3 m, how much work is done?
  3. Learners explain in their own words why pushing a wall (without movement) is not “work” in science.
  4. Learners give one example of scientific work in daily life.

Notes (Expanded & Detailed):

  • In science, work only happens when a force causes movement of an object in the same direction as the force.
  • Formula: Work = Force × Distance moved in the direction of the force.
  • The unit of work is the Joule (J). One Joule is the work done when a force of one Newton moves an object one meter.
  • Everyday language: “work” may mean effort or feeling tired (e.g., reading for long hours), but in science, if there is no movement, there is no work.
  • Examples:
  1. Lifting a 5 kg bucket 2 meters high:
    • Weight = 5 kg × 9.8 N/kg = 49 N.
    • Work = 49 N × 2 m = 98 J.
  2. Dragging a chair with a force of 20 N over 5 m:
    • Work = 20 N × 5 m = 100 J.
  3. Holding a bag in your hands without moving = 0 J (no distance moved).

Extra Practical Activity / Assignment:

  • Learners calculate the work done in these cases:
  1. A boy pulls a toy with a force of 15 N for 4 m.
  2. A girl lifts a 10 kg water container (weight = 98 N) to a height of 1.5 m.
  • Homework: Learners find 3 activities at home where scientific work is done and calculate the approximate work (using estimated forces and distances).

C – Consolidation (Conclusion & Assessment)
Time: 5–10 minutes
Summary: Recap the formula for work, units, and examples. Highlight the difference between everyday and scientific definitions of work.

Evaluation Method (Expanded)
Exit slip/quiz: Write the formula for work and give one example. Teacher collects slips and provides oral feedback.
Assignment (Expanded): Measure the force required to lift an object at home and calculate the work done.
Follow-up Activity: Record examples of work done by family members and calculate approximate work using the formula.
Differentiation / Inclusive Strategies: Provide step-by-step guidance for calculations, use visual aids, and group activities for learners needing support.