Lesson Notes By Weeks and Term v4 - JHS 3
FORCE AND MOTION
Download the Lessonotes Mobile Ghana app for faster lesson access on Android and iPhone.
FORCE AND MOTION
Download the Lessonotes Mobile Ghana app for faster lesson access on Android and iPhone.
Subject: Science
Class: JHS 3
Term: 2nd Term
Week: 12
Grade code: B9.4.4.1.1
Strand code: 4
Sub-strand code: 4
Content standard code: B9.4.4.1
Indicator code: B9.4.4.1.1
Theme: FORCES AND ENERGY
Subtheme: FORCE AND MOTION
This page supports the lesson note with a companion video and a short classroom-ready summary.
For class groups and homework, share this lesson page so learners also get the summary, objectives, and full lesson context.
In everyday life in Ghana, we often say something is “pressing” or “putting pressure” on something else: pumping a bicycle or car tyre, squeezing a balloon, drinking sobolo with a straw, washing a car with a pressure washer at a washing bay, or even wearing high-heeled shoes that sink into soft ground. All these situations involve pressure, which is how a force is spread over an area. Understanding pressure helps learners explain why sharp objects cut easily, why tyres need the right air pressure, and why dams and water tanks must be strong at the bottom.
A. Meaning of Pressure Pressure is the force acting per unit area on a surface. If the same force acts on a smaller area, the pressure is greater. If the same force acts on a larger area, the pressure is smaller.
Formula: \[ P=\frac{F}{A} \] Where: \(P\) = pressure \(F\) = force (in newtons, N) \(A\) = area (in square metres, m²)
SI unit of pressure: pascal (Pa) \[ 1\text{ Pa} = 1\text{ N/m}^2 \]
Other common units (for awareness): kPa, bar, atm (often used for tyres and weather), but in school calculations we use Pa.