A mirror and a source of light are situated at the origin O and a point on OX respectively. A ray of light from the source strikes the mirror and is reflected. If the DR's of the normal to the pl

Question

A mirror and a source of light are situated at the origin O and a point on OX respectively. A ray of light from the source strikes the mirror and is reflected. If the DR's of the normal to the plane of the mirror are 1, -1,1, then the DC's of the reflected ray are

TestHub · Accepted Answer

The incident ray travels from the source on OX towards 0 , along d = ( − 1 , 0 , 0 ) . The unit normal is n ^ = 3 ​ 1 ​ ( 1 , − 1 , 1 ) . The reflected direction is d − 2 ( d ⋅ n ^ ) n ^ = ( − 1 , 0 , 0 ) + 3 2 ​ ( 1 , − 1 , 1 ) = ( − 3 1 ​ , − 3 2 ​ , 3 2 ​ ) .

Mathematics - 3D-Coordinate Geometry Question with Solution | TestHub

Options:

Doubts & Discussion