HS – School of Science – Unit 25 – Light – Moodle


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Designed By:
Christian Alas
Created and illustrated By:
Angelo Romero and Camilo Sanabria


Light travels in visible waves that we see as rays of light. A photon is a basic unit of light. It is a tiny particle of electromagnetic energy. Some objects absorb light rays and others bounce the rays back.

Reflection is when light is bounced back from a surface. Light rays are reflected back at the same angle that they hit the surface. If it is not a smooth surface, then the light rays could be reflected in different directions.

Mirrors are made to reflect by using smooth surfaces like glass. The reflection off of a smooth surface is called a regular reflection. A concave lens is a lens that is thinner in the middle than the outer area. A convex lens is thicker in the middle than the outer area.

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A lens is a material that refracts light and is usually made up of glass or other transparent materials.

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The focal point is the point at which light beams meet after passing through a convex lens or reflecting from a concave mirror. When light travels from one substance to another, the light rays change direction.

Refraction is the bending of light. The bending of light occurs because light travels at different speeds when going through different substances. When light travels from one medium to another it becomes refracted or bent light. Light travels faster through air than it does through water.

A great visual illustration of the bending of light occurs when light travels through both water and glass. If you place a pencil inside a glass filled with water and look at the pencil through the glass, the pencil will appear to be broken.

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Light bends as it goes through the glass, the water and the air creating an optical illusion.

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1. What is the writer’s main idea?


2. What example supports the writer’s main idea?


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3. How does the example help the writer’s argument?


4. What do you think about the story?


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