Measurement and Units

Grade 10 · Physics

Semester 1 | Period 1 | Week 3

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Subject: Physics

Semester: 1

Period: 1

Week: 3

School Name:

Teacher’s Name:

Subject: Physics

Grade Level: Grade 10

Week & Period: Week 3, Period I

Date:

Topic: Measurement and Units
Sub-topic: Fundamental and Derived Quantities, Metric Prefixes, Systems of Measurement

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

  1. Identify fundamental and derived quantities and their units;
  2. Describe different systems of measurement;
  3. Use metric prefixes appropriately;
  4. Convert between units in metric system.

Previous Knowledge: Learners understand the difference between scalar and vector quantities and can perform basic unit conversions.

Instructional Materials:

  • Table/chart showing fundamental and derived quantities
  • Flashcards with metric prefixes
  • Conversion worksheets
  • Rulers, measuring tape, beaker, weighing balance
  • Board for solving conversion problems

Anticipation (Warm-Up) – 5 minutes Ask:

  • “If I measure your height in inches and someone else uses centimeters, who is correct?”
  • “Why do scientists use the same unit system around the world?” Introduce the importance of standard units in science.

Building Knowledge (Main Lesson) – 25 minutes

  1. Systems of Measurement:
    • SI System (International System of Units) is most commonly used in Physics
    • Other systems: CGS (centimeter-gram-second), MKS (meter-kilogram-second)
  2. Fundamental Quantities and Units:
    • Length (meter, m)
    • Mass (kilogram, kg)
    • Time (second, s)
    • Electric current (ampere, A)
    • Thermodynamic temperature (kelvin, K)
    • Luminous intensity (candela, cd)
    • Amount of substance (mole, mol)
  3. Derived Quantities and Units:
    • Area (m²), Volume (m³), Density (kg/m³), Speed (m/s), Acceleration (m/s²), Force (N = kg·m/s²), Pressure (Pa), Work (J)
  4. Metric Prefixes:
    • kilo (10³), centi (10⁻²), milli (10⁻³), micro (10⁻⁶), mega (10⁶), etc.
    • Examples:
      • 2 km = 2 × 10³ m = 2000 m
      • 5 cm = 5 × 10⁻² m = 0.05 m
  1. Conversion Practice:
    • Convert 200 cm to m = 200 ÷ 100 = 2 m
    • Convert 3.5 kg to g = 3.5 × 1000 = 3500 g
    • Convert 4500 mL to L = 4500 ÷ 1000 = 4.5 L

Learners’ Activities:

  • Match quantities with their units (e.g., Speed – m/s)
  • Complete a conversion worksheet
  • Use metric rulers, measuring cylinders and balances to measure length, volume, and mass
  • Classify quantities as fundamental or derived

Consolidation (Assessment) – 10 minutes Oral Questions:

  1. What is a derived quantity? Give two examples.
  2. Convert 1200 mL to litres.
  3. Name three fundamental quantities and their units.

Written Activity:

  • List 5 fundamental and 5 derived quantities with units
  • Convert: a. 3.2 km to m b. 0.45 g to mg c. 2.5 L to mL

Homework / Assignment:

  1. Write the full SI units of the following: Work, Acceleration, Volume, Density
  2. Convert the following: a. 0.007 kg to g b. 560 cm³ to m³ c. 0.02 MW to W
  3. Create a table showing at least 10 metric prefixes with their powers of ten and symbols.

Notes – Detailed and Explained

  • Fundamental quantities are the basic physical quantities that cannot be broken down further.
  • Derived quantities are formed from combinations of fundamental quantities.
  • SI units provide a global standard of measurement for clarity in communication.
  • Metric prefixes simplify working with very large or small numbers.
  • Prefixes like kilo-, centi-, milli-, and micro- are widely used in scientific calculations.
  • Examples of conversions and measurements help build accuracy in experimental physics.

Expanded Notes / Instructions:

  • Show how force is derived: Force = mass × acceleration (kg × m/s² = N)
  • Display real-life examples: measuring fuel in liters, traveling in km, weight in grams.
  • Let learners practice conversions using simple tools: weigh a pen, measure classroom items.

Inclusive / Differentiation:

  • Hands-on measuring tools for kinesthetic learners
  • Group conversions for peer tutoring
  • Visual metric tables and flashcards for visual learners
  • Encourage learners to develop their own mnemonic devices for metric prefixes

Teacher’s Reflection (Post-Lesson Questions):

  • Did students understand the distinction between fundamental and derived quantities?
  • Were they able to apply metric prefixes in real conversions?
  • Did hands-on practice improve their understanding?
  • Who needs extra support in unit conversions or identifying quantities?