Lesson Notes By Weeks and Term v4 - SHS 2
BASIC PHYSICS
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BASIC PHYSICS
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Subject: Physics
Class: SHS 2
Term: 1st Term
Week: 4
Grade code: 2.1.1.LI.2
Strand code: 1
Sub-strand code: 1
Content standard code: 2.1.1.CS.1
Indicator code: 2.1.1.LI.2
Theme: MECHANICS AND MATTER
Subtheme: BASIC PHYSICS
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Welcome, future engineers, scientists, and problem-solvers! Today, we are learning a powerful technique that is like a secret code for understanding the universe. It’s called Dimensional Analysis. Have you ever wondered how scientists come up with famous equations like E=mc²? While the full theories are complex, one of the first checks they perform is to ensure the "units" or "dimensions" on both sides of an equation match up. You can't say that the distance to Kumasi (in kilometres) is equal to the weight of a bag of kenkey (in kilograms). They are different types of quantities.
A. What are Physical Dimensions?
In physics, we measure quantities. Every quantity has a fundamental nature, which we call its dimension. We represent these dimensions with specific symbols, usually capital letters in square brackets.
There are seven base quantities from which all others are derived. For our level, we will focus on the three most common ones in mechanics:
| Base Quantity | Symbol for Quantity | Dimension | SI Unit | | :------------ | :------------------ | :-------- | :------ | | Mass | m | [M] | kilogram (kg) | | Length | l, d, h, r | [L] | metre (m) | | Time | t | [T] | second (s) |