Question

A plane mirror is placed along the x-axis facing negative y-axis. The mirror is fixed. A point object is moving with $3\hat{i}+4\hat{j}$ in front of the plane mirror. The relative velocity of image with respect to its object is

• A. $-8\hat{j}$
• B. $8\hat{j}$
• C. $3\hat{i}-4\hat{j}$
• D. $-6\hat{i}$

Answer 1

The correct option is A $-8\hat{j}$

$\overrightarrow{V_I}=3\hat{i}+4\hat{j}\overrightarrow{V_R}=3\hat{i}-4\hat{j}\therefore \overrightarrow{V_R}-\overrightarrow{V_I}=-8\hat{j}$