6th June 2020



DATE: 2nd June 2020


SUBJECT: Physics

Topic: Revision on fundamental and derived quantities and units

Reference: Essential physics.

Learning objectives: At the end of this lesson, the students should be able to:

  1. Distinguish between fundamental and derived units.
  2. Distinguish between fundamental and derived quantities.

Introduction: Physical quantities are measurable physical attributes of matter. These physical quantities are divided into two along with their units.


Fundamental Units: These are the accepted standard units or measures in which measurement is made. Some of the important fundamental units are:

  1. Kelvin
  2. Ampere

Derived Units: These are new units gotten or derived from the fundamental units. They are obtained from the combination of two or more fundamental quantities. Examples are:

  1. Meter per second (ms-1)
  2. Meter per second square (ms-2)
  3. Meter cubic (m3)
  4. Kilogram per second square kgm/s-2 or N etc.

Fundamental quantities (Basic)

These are independent or the origin of other quantities in physics. They are quantities that provide the standard units of measurement. Examples are:

  1. Mass
  2. Length
  3. Time
  4. Current
  5. Temperature

Derived quantities –

Derived quantities are obtained from the combination of two or more fundamental quantities.

  1. Speed
  2. Velocity
  3. Acceleration
  4. Area
  5. Volume
  6. Force
  7. Work

The difference between mass and weight

Mass is defined as the quantity of matter in a body. This gives the exact value of a substance no matter where it is measured.

Weight is defined as the earth pull of the body. i.e. force acting on a body due to gravity.


  1. Name three fundamental quantities in science and their respective units.
  2. Name the instrument that can be used to measure the following: (a) Time

(b) Weight of an object

(c) Length

(d) Mass

(e) Temperature

  1. Name 4 derived quantities and 4 fundamental quantities.
  2. Name some fundamental quantities and some derives unites.
  3. What is the difference between mass and weight?
  4. Write the difference between fundamental quantities and derived quantities.