Lesson Notes By Weeks and Term v4 - SHS 3
BASIC PHYSICS
Download the Lessonotes Mobile Ghana app for faster lesson access on Android and iPhone.
BASIC PHYSICS
Download the Lessonotes Mobile Ghana app for faster lesson access on Android and iPhone.
Subject: Physics
Class: SHS 3
Term: 1st Term
Week: 8
Grade code: 3.1.1.LI.5
Strand code: 1
Sub-strand code: 1
Content standard code: 3.1.1.CS.3
Indicator code: 3.1.1.LI.5
Theme: MECHANICS AND MATTER
Subtheme: BASIC PHYSICS
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.
For thousands of years, long before telescopes and satellites, people in Ghana and all over the world have looked up at the night sky with wonder. The stars, "shooting stars," and other objects were not just beautiful lights; they were our first calendar, our first map, and the source of our greatest stories. In this lesson, we will explore these celestial objects—comets, asteroids, and constellations—not just as scientific phenomena, but as powerful forces that have shaped Ghanaian culture, farming, navigation, and our understanding of the universe.
Part 1: Distinguishing Celestial Objects
This section follows the "Enquiry Learning" exemplar. It is best delivered using videos and pictures from the internet/YouTube projected for the class.
A. Comets: The "Dirty Snowballs" of Space Definition: A comet is a small celestial body made of ice, dust, and rock that orbits the Sun. Composition: Think of a comet as a "dirty snowball." Its core, called the nucleus, is a frozen mixture of water ice, frozen gases (like carbon dioxide, methane, ammonia), rock, and dust. Orbit: Comets have highly elliptical (oval-shaped) orbits. This means they travel far out into the solar system and then swing back in close to the Sun. This journey can take from a few years to thousands of years. Halley's Comet, for example, returns every 76 years. Key Features: When a comet gets close to the Sun, the heat causes the ice to sublimate (turn directly from solid to gas). This creates two distinct features: Coma: A glowing, hazy cloud of gas and dust that forms around the nucleus. Tail: The solar wind (a stream of particles from the Sun) pushes the gas and dust away from the coma, forming one or two tails. The ion tail (gas) always points directly away from the Sun, while the dust tail (heavier particles) curves slightly along the comet's orbital path.
B. Asteroids: The Rocky Wanderers Definition: An asteroid is a small, rocky object that orbits the Sun. Composition: They are made mostly of rock and metals, like iron and nickel. They do not have the ice content of comets. Location: Most asteroids are found in the Asteroid Belt, a region of space between the orbits of Mars and Jupiter. Orbit: Their orbits are generally more circular than those of comets and are confined mainly to the Asteroid Belt. Size: They range in size from a few metres to hundreds of kilometres across. The largest is Ceres, which is about 940 km in diameter.