question_answer

A man on the top of a cliff 100 m high observes the angles of depression of two points on the opposite sides of the cliff as 30° and 60°, respectively. Then, the distance between the two points is

A) 400 m                   

B) \[W\]

C) \[\frac{4W}{3}\]              

D) None of these

Correct Answer: B

Solution :

                Let PQ be the cliff and A and B be the points under observation. In \[{{Q}_{2}}\]                 \[{{Q}_{1}}{{R}_{2}}\ne {{Q}_{2}}{{R}_{1}}\] \[{{Q}_{1}}{{R}_{2}}={{Q}_{2}}{{R}_{1}}\]              \[s=\frac{{{t}^{2}}}{4}\]                 ?.. (i) And in \[T\propto V\]                 \[T\propto {{V}^{2}}\] \[T\propto \frac{1}{{{V}^{2}}}\] \[T\propto \frac{1}{V}\]                                ?? (ii) On adding Eqs. (i) and (ii), we get \[\text{6}\times \text{1}{{0}^{-\text{7}}}\text{A}-{{\text{m}}^{\text{2}}}\]