Lesson Notes By Weeks and Term v4 - SHS 1
POWERING THE FUTURE WITH ENERGY FORMS
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POWERING THE FUTURE WITH ENERGY FORMS
Download the Lessonotes Mobile Ghana app for faster lesson access on Android and iPhone.
Subject: General Science
Class: SHS 1
Term: 2nd Term
Week: 13
Grade code: 3.3.1.LI.2
Strand code: 3
Sub-strand code: 1
Content standard code: 3.3.1.CS.1
Indicator code: 3.3.1.LI.2
Theme: VIGOUR BEHIND LIFE
Subtheme: POWERING THE FUTURE WITH ENERGY FORMS
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Light is a fundamental form of energy that shapes our world. From the moment we wake up and see our reflection in a mirror to using our mobile phones to take pictures, we are interacting with the principles of light, mirrors, and lenses. In Ghana, understanding these concepts is vital. It helps us understand how a car's side mirror keeps a driver safe on the Accra-Kumasi highway, why an elder in our family might need reading glasses ("spectacles"), and how fibre optic cables laid by companies like MTN and Vodafone bring high-speed internet to our homes and schools.
This section covers the core scientific principles needed to understand the topic. Part A: Reflection of Light and Mirrors
Reflection is the bouncing back of light when it strikes a surface.
Laws of Reflection: First Law: The incident ray, the reflected ray, and the normal at the point of incidence all lie on the same plane. Second Law: The angle of incidence (i) is equal to the angle of reflection (r). *(The normal is an imaginary line drawn perpendicular, i.e., at 90°, to the reflecting surface at the point where the light ray hits it.)*
Types of Mirrors: Plane Mirror: A mirror with a flat reflective surface. Image Characteristics: The image formed is: Virtual: Cannot be formed on a screen. Erect: Upright, the same way up as the object. Laterally Inverted: Left appears as right and vice versa. Same size as the object. Located as far behind the mirror as the object is in front of it. Spherical Mirrors: Mirrors that are a part of a hollow sphere. Concave Mirror (Converging): The reflecting surface curves inwards. It converges (brings together) parallel rays of light to a focal point. Convex Mirror (Diverging): The reflecting surface curves outwards. It diverges (spreads out) parallel rays of light so that they appear to come from a focal point behind the mirror.