question_answer

A man is sitting in a room at 2 m from a wall \[{{W}_{1}}\] wants to see the full height of the wall \[{{W}_{2}}\] behind him 4 m high and 6 m away from the facing wall \[{{W}_{1}}\]. What is the minimum vertical length of mirror on the facing wall required for the purpose?

A) 4 m                         

B) 2 m

C) 3 m

D) 1 m

Correct Answer: D

Solution :

[d] Let the min. length of mirror be L          \[\frac{L}{4}=\frac{2}{8}\Rightarrow L=1m\]