What happens to a light ray if it is incident on an object's surface along the normal?
The incident ray retraces its original path.
The incident ray is reflected perpendicular to the normal.
The incident ray is reflected at an angle to the normal.
The incident ray is not reflected.

Question

What happens to a light ray if it is incident on an object's surface along the normal?
The incident ray retraces its original path.
The incident ray is reflected perpendicular to the normal.
The incident ray is reflected at an angle to the normal.
The incident ray is not reflected.

rina.r · Answer

Its A 
BUT LOOK AT OTHER OPTIONS AS WELL
The answer depends on the type of substance you are talking about.
If the object is capable of allowing light through it then the light ray passes through it without any deviation.
If the object is like mirror the answer is OPTION A
If the object is neither reflecting nor transmitting type then the answer is OPTION D

rina.r · Answer

http://answers.yahoo.com/question/index?qid=20130626030258AAEG11g