Question

A plane mirror is on $y-z$ plane facing positive $x-$ axis. A point object is present at $(10,5)$. The mirror is translated by $2$ units along positive $x$ and $3$ units along positive $y-$ direction. Final image of the point object is at

• A. $(-10,-5)$
• B. $(-8,-3)$
• C. $(-6,-5)$
• D. $(-6,-2)$

Answer 1

The correct option is A $(-10,-5)$

Given that,

plane mirror is on y-z plane facing x-axis. Object is present at (10, 5) .

Now, the mirror is translated by 2 units in positive x-axis and 3 units in positive direction.

Let the image be at Q (x, y). As P is image of Q, M will be its midpoint.

$\Rightarrow (\frac{x+10}{2},\frac{y+5}{2})=(2,5)\Rightarrow x+10=4,y+5=10\Rightarrow x=-6,y=5\Rightarrow Q=(-6,5)$

Therefore, final image will form at (-6, 5)