Chapter 8.7, Problem 6WE

To determine

the ground distance from the airport to the plane.

Answer to Problem 6WE

The ground distance from the airport to the plane is 60,000 ft.

Explanation of Solution

Given:

The airplane flying at a height, 30,000 ft, and airplane will approach an airport at the angle of depression of $3°$ .

Calculation:

Assume the distance from the airport to the plane is $x$ .

By the ratio of sides from the right − angled triangle, we can write:

  $\begin{array}{l}\tan \theta =\frac{\text{Opposite side}}{\text{Adjacent side}},\\ \Rightarrow \tan 3°=\frac{30000}{x},\\ \Rightarrow x=\frac{30000}{0.052},\\ \Rightarrow x=60,000\text{ ft}\text{.}\end{array}$