In Science, we have been looking at light this half term.
As part of this topic, the children planned and set up experiments using torches, mirrors, card with holes in and other opaque objects. They were challenged to prove not only that light travels in straight lines but also that it can change direction when reflected from an object. In addition, they were able to investigate how rays of light are reflected off the surface of a smooth, shiny surface like a mirror at the same angle at which they hit it.
They then built on this knowledge to explore how refraction occurs. Light passes through different materials at different speeds; for example, light travels faster through air than it does through water. When light moves from air to water, it slows down and that can cause it to change direction. This is caused ‘refraction’. They observed refraction first hand by drawing a horizontal arrow on a piece pf paper, which they held behind a glass. Refraction causes the arrow to appear to have flipped 180 degrees, so that it is pointing in the opposite direction! Refraction also causes a pen to look like it has been cut in half when placed in water and a pencil to look like it is curved, when in fact it is straight!
