TERM/WEEK: THIRD TERM/WEEK 1
DATE: 2nd June 2020
CLASS: J.S.S 1
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:
- Distinguish between fundamental and derived units.
- 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.
Presentation
Fundamental Units: These are the accepted standard units or measures in which measurement is made. Some of the important fundamental units are:
- Kelvin
- 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:
- Meter per second (ms-1)
- Meter per second square (ms-2)
- Meter cubic (m3)
- 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:
- Mass
- Length
- Time
- Current
- Temperature
Derived quantities –
Derived quantities are obtained from the combination of two or more fundamental quantities.
- Speed
- Velocity
- Acceleration
- Area
- Volume
- Force
- 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.
Exercises/assignment
- Name three fundamental quantities in science and their respective units.
- Name the instrument that can be used to measure the following: (a) Time
(b) Weight of an object
(c) Length
(d) Mass
(e) Temperature
- Name 4 derived quantities and 4 fundamental quantities.
- Name some fundamental quantities and some derives unites.
- What is the difference between mass and weight?
- Write the difference between fundamental quantities and derived quantities.