# Light is Reflecting-EASYYYY PROBLEM! but help needed.

[SOLVED] Light is Reflecting-EASYYYY PROBLEM! but help needed.

## Homework Statement

Figure 33-47 shows light reflecting from two perpendicular reflecting surfaces A and B. Find the angle between the incoming ray i and the outgoing ray r'.
The figure is attached to this thread!

## Homework Equations

angle of incedence = angle of reflection

## The Attempt at a Solution

don't know where to start from

#### Attachments

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Dick
Homework Helper
The two acute angles in a right triangle sum to 90 degrees. They are complementary. Use that.

oooo well thank you Dick, but how in the world can you find out those two angles, if no other values of angles are given. like i no the normal line equals to 90 degrees also, but how can you find the angles.

Dick
Homework Helper
The angle between the incoming and the outgoing ray is the difference between the angle theta in your picture and the angle r' makes with the horizontal surface B (call it phi). Start labelling all of the angles you can find as either theta or 90-theta. You should be able to show phi=theta.

and congratulations Dick on receiving the 2007 PF Award!

Dick
Homework Helper
so the "angle between the incoming and the outgoing ray" can be labeled like beta so basically beta=theda-phi?
Thanks for the congrats. Yes, theta and phi are the angles the incoming and outgoing make with a horizontal line. If those are equal, they are parallel.

whoA! wait a second. i thought tha theda made an angle with the vertical line and normal line. like in teh diagram= that shows what theda is.

Dick
Homework Helper
'teh diagram' that I'm looking at shows theta as the angle between the incoming ray and the normal to the vertical reflector - which is horizontal.

Dick