# Physics

posted by .

Subject: Light and Geometric Optics

Question: Where must a light source be placed in front of a concave mirror for
a) light energy to be concentrated to a single point
b)the light to be reflected in a parallel beam?

• Physics -

a) Anywhere beyond the focal point will do. If you want the light concentrated at the same location as the source, the distance must be 2f.

b) At the focal point

• Physics -

Thank you!

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