Lesson Notes By Weeks and Term v4 - SHS 3
WAVE
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WAVE
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Subject: Physics
Class: SHS 3
Term: 1st Term
Week: 18
Grade code: 3.2.2.LI.3
Strand code: 2
Sub-strand code: 2
Content standard code: 3.2.2.CS.1
Indicator code: 3.2.2.LI.3
Theme: ENERGY
Subtheme: WAVE
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This lesson focuses on the mathematical relationship that governs how lenses form images. Lenses are fundamental to our daily lives in Ghana; they are in our mobile phone cameras (like Tecno, Infinix, Samsung), the projectors used in our schools and churches, and most importantly, in the spectacles ("medo me aniso") that help many of our parents, grandparents, and friends to see clearly. By understanding the lens formula, we can predict precisely where an image will be formed, how large it will be, and what its characteristics are. This knowledge is not just for passing WASSCE; it is the foundation for understanding optics, a field crucial for technology and medicine.
This section contains the core content for the lesson. It is designed to be taught directly to the students. A. The Thin Lens Formula
The thin lens formula is a mathematical equation that relates the focal length of a lens (`f`), the distance of the object from the optical centre (`u`), and the distance of the image from the optical centre (`v`).
The formula is: ``` 1/f = 1/u + 1/v ```
Where: `f` is the focal length of the lens. This is a fixed property of the lens. `u` is the object distance. This is the distance from the object to the optical centre of the lens. `v` is the image distance. This is the distance from the image formed to the optical centre of the lens.