Lesson Notes By Weeks and Term v4 - SHS 1
INTRODUCTION TO PHYSI CS
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INTRODUCTION TO PHYSI CS
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Subject: Physics
Class: SHS 1
Term: 1st Term
Week: 5
Grade code: 1.1.1.LI.2
Strand code: 1
Sub-strand code: 1
Content standard code: 1.1.1.CS.2
Indicator code: 1.1.1.LI.2
Theme: MECHANICS AND MATTER
Subtheme: INTRODUCTION TO PHYSI CS
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Welcome, future scientists and engineers! Today, we are exploring the very foundation of physics: understanding the language that describes our universe. Just like we use letters to build words, physics uses fundamental "ingredients" to describe everything we can measure. This topic, called Dimensional Analysis, is like being a detective. It helps us check if our physics formulas are correct and understand how different ideas like speed, force, and energy are related. Whether you are calculating the speed of a tro-tro, understanding the force needed to pound fufu, or figuring out the energy from the sun hitting a solar panel, the principles we learn today are essential.
A. What are Physical Quantities?
A physical quantity is any property of a material or system that can be quantified by measurement. In simple terms, if you can measure it, it's a physical quantity. Examples: Your height, the time it takes to walk to school, the mass of a bag of rice, the temperature of a room.
Physical quantities are divided into two main groups: Fundamental Quantities: These are the basic building blocks that are independent and cannot be expressed in terms of other quantities. In mechanics, we focus on three: Mass: The amount of matter in an object. Length: The measure of distance between two points. Time: The interval between two events. Derived Quantities: These are quantities that are formed by combining fundamental quantities through multiplication or division. Example: Speed. To find speed, you measure a distance (Length) and divide it by the time taken. So, speed is *derived* from Length and Time. B. What are Dimensions?
The dimension of a physical quantity is a way of expressing its nature in terms of the fundamental quantities, without worrying about the specific units (like metres or feet, kilograms or pounds). We use specific symbols to represent the fundamental dimensions: Dimension of Mass = [M] Dimension of Length = [L] Dimension of Time = [T]