A plane is flying at 300 meters altitude. A man from the plane observes two man in a straight line on the same slides of the plane on the ground with angles of depression as 30° and 60°. The distance between two men is? (\(\sqrt {3}\) = 1.732) |
385.2 364.5 346.4 345.5 |
346.4 |
C is man 1 and D is man 2. CD is the distance between two men. In ΔABD → Tan 30° = \(\frac{300}{BD}\) BD = \(\frac{300}{\frac{1}{\sqrt {3}}}\) In ΔABC → Tan 60° = \(\frac{300}{BC}\) BC = \(\frac{300}{\sqrt {3}}\) = 100\(\sqrt {3}\) Distance between two men on the ground CD = BD - BC = 300\(\sqrt {3}\) - 100\(\sqrt {3}\) = 200\(\sqrt {3}\) = 200 × 1.732 = 346.4 |