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Q & A: The Law of Reflection

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Most recent answer: 10/22/2007
When light hit a mirror, does it reflect off at a 90 degree?
- teckkian (age 12)
Tampines North Primary School, SIngapore
Teckkian -

No, light will not necessarily be reflected off a mirror at a 90 degree angle. When light is reflected by a mirror, it íbouncesí off at the same angle from the mirror that it came in at. Itís like this:


(from )

In the picture above, the angle is roughly 90 degrees. Thatís because the angle of incidence (the angle that it comes in at) is about 45 degrees. Since the angle of reflection (the angle that it goes out at) is the same, the total angle is 45+45=90. If the light comes in at a different angle, though, it will be bent accordingly:

Light coming in at different angle
(also from )


(published on 10/22/2007)

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