Drawing ray diagrams 1

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Drawing ray diagrams 1
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• Ray diagrams can help you work out what sort of
  image a lens and object will produce.

3

• Use an arrow to represent the object.
• Even though light is reflected off the whole
  object, just think about the light coming from
  the tip.

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• Think about three paths of light.
• Light passing through the centre of the lens
  continues in a straight line.

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1. Light travelling parallel to the principal axis
   is refracted so that it passes through the
   principal focus on the other side.

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1. Light passing through the principal focus is
   refracted so that it comes out parallel to the
   principal axis.

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• This symbol represents a converging (convex)
  lens.
• It is often used when drawing ray diagrams as an
  alternative to drawing a full lens.