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Light travels in straight lines
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In this lesson we introduce some of the properties of light. Firstly, we look at how light travels in straight lines by
exploring solar eclipses. A solar eclipse happens when the moon moves between the earth and the sun and the
sun’s rays are then unable to reach the earth. Some traditional myths and beliefs regarding eclipses are also
explored in this lesson.
Simple ray diagrams are drawn to help explain how the light has travelled in a straight line. To further explain
how light travels in straight lines, a simple pin-hole camera is constructed and the image formed is studied.
We suggest that the learners build their own pin-hole cameras during the lesson in order to carry out their own
investigations. We begin a debate about the nature of light. Light can either be modelled as a wave or as a
stream of particles. We suggest that you get learners to form their own opinions (which they need to justify)
about these ideas. We suggest you continue this debate throughout the series.










english first additional language
i really enjoy mindset lessons