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Mission RL8 Converging Lenses - Ray Tracing

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 The Question

The diagram shows an 'object arrow' (drawn in RED) and five sets of incident and refracted rays (numbered 1, 2, 3, 4, and 5). Which of these sets are correct? List all that apply ... .

 Define Help

Definition of an Image:
An image is a likeness of an object that appears at a location in space where it would seem to every observer as though light from the object was coming from.

 Physics Rules

Converging Lenses - Rules of Refraction
Light refracts at any boundary - including those that bound a lens material - according to Snell's law. For converging lenses, some generalizations can be made to simplify ray construction. They are:
  • An incident ray traveling parallel to the principal axis will refract and pass through the focal point on the opposite side of the lens.
  • An incident ray traveling through the focal point on the way to the lens will refract and travel parallel to the principal axis.
  • An incident ray traveling through the exact center of the lens will refract upon entering the lens and upon leaving the lens and continue traveling in its original direction.

 Think About It

Certain rays of light - known as principal rays - refract through a converging lens in a rather predictable manner. These rays are described by the rules of refraction in the Know the Law section. You will find at least two of these principal rays on the diagram. There are other incident rays whose refractive behavior cannot be predicted simply by their direction of travel. Nonetheless, it is known that all the light that starts at the same location will pass through the lens and intersect at the same location. Any ray of light that intersects at the same location where the predictable principal rays intersect is correctly drawn.

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