Question

The angular depressions of the top and foot of a chimney as seen from the top of a second chimney, which is 150 m high and standing on the same level as the first are $\phi$ respectively, then the distance between their tops when $\tan \phi = \frac { 5 } { 2 }$ is

• A. $\frac { 150 } { \sqrt { 3 } }$ metres
• B. $100 \sqrt { 3 }$ metres
• C. 150 metres
• D. 100 metres

Answer 1

Answer: (D)

100 metres

Answer 2

Also,

Hence, $x = \sqrt { 80 ^ { 2 } + 60 ^ { 2 } }$= 100 m