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: 2
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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This lesson introduces Archimedes' Principle, a fundamental concept in fluid mechanics. We will explore why objects feel lighter in water, why some things float while others sink, and how to quantify the upward force (upthrust) that fluids exert. This principle is not just a theory in a book; it explains everyday experiences, from a canoe floating on the Volta River to feeling buoyant while swimming at Labadi Beach. Understanding this helps us design ships, check the purity of liquids, and appreciate the physics governing our world.
A. The Experience of Buoyancy
Think about the last time you were in water—a pool, a river, or the sea. Did you notice you felt lighter? Or have you ever tried to lift a heavy stone from the bottom of a river? It feels much easier to lift while it's in the water than when you pull it out into the air. This "lifting" help you feel from the water is a force. We call this upward force Upthrust or Buoyant Force. Definition: Upthrust is the upward force exerted by a fluid (a liquid or a gas) that opposes the weight of an object immersed in it.
This force is the reason why boats float and why you feel lighter in water. B. Archimedes' Principle
An ancient Greek scientist named Archimedes discovered the rule that governs this upthrust.