Lesson Notes By Weeks and Term v4 - SHS 2
MEASUREMENT
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MEASUREMENT
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Subject: Mathematics
Class: SHS 2
Term: 2nd Term
Week: 8
Grade code: 2.3.2.LI.2
Strand code: 3
Sub-strand code: 2
Content standard code: 2.3.2.CS.2
Indicator code: 2.3.2.LI.2
Theme: GEOMETRY AROUND US
Subtheme: MEASUREMENT
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This lesson introduces the concepts of angles of elevation and depression, which are practical applications of trigonometry in our daily lives. From building our houses and bridges to navigating airplanes and ships, understanding these angles helps us measure heights and distances that we cannot easily reach. In Ghana, surveyors mapping land for a new road in the Eastern Region, fishermen estimating their distance from the Cape Coast castle, or engineers setting up a communication mast in Kumasi all use these principles. This lesson will equip learners with the skills to model and solve such real-world problems.
A. Fundamental Terms
Before we can understand angles of elevation and depression, we must know these two key lines: Horizontal Line: This is a perfectly flat line that is parallel to the ground or the horizon. Imagine the surface of a calm body of water like the Volta Lake; that's a horizontal surface. Line of Sight: This is an imaginary straight line from the eye of an observer to the object they are looking at. B. Angle of Elevation
The Angle of Elevation is the angle formed between the horizontal line and the line of sight when an observer is looking UP at an object. Think of it this way: "Elevate" means to raise or lift up. So, you lift your eyes up from the horizontal.
Diagram: