A two-dimensional light ray is represented by the vector before it strikes a…

PHYSICS · Single correct · AP · Physics 2: Algebra-based · Geometric Optics · Geometric Optics

Problem

A two-dimensional light ray is represented by the vector

\mathbf v = 3\hat{\imath}-4\hat{\jmath}

before it strikes a perfectly reflecting surface that lies along the line

y = x

. Which vector best represents the direction of the reflected ray? (a)

3\hat{\imath}+4\hat{\jmath}

(b)

-4\hat{\imath}+3\hat{\jmath}

(c)

4\hat{\imath}-3\hat{\jmath}

(d)

-3\hat{\imath}+4\hat{\jmath}