question_answer

When a plane mirror is placed horizontally on a level ground at a distance of \[60m\] from the foot of a tower, the top of the tower and its image in the mirror subtend an angle of \[90{}^\circ \] at the eye. The height of the tower will be [CPMT 1984]

A)            \[30m\]                                  

B)            \[60m\]

C)            \[90m\]                                  

D)            \[120m\]

Correct Answer: B

Solution :

                   \[\tan 45{}^\circ =\frac{h}{60}\] \[\Rightarrow h=60\,m\]