Chapter 9.7, Problem 2E

To determine

To Find: the distance of horizon if a lookout climbs high in the rigging of a sailing ship to a point $36\text{m}$ above the water line.

Answer to Problem 2E

  $20\text{ km}$

Explanation of Solution

Given:

Height above the surface of earth is $36\text{m}$ .

Calculation:

Using the formula.

  $\begin{array}{l}{\left(\text{Distance}\right)}^2=12,800,000\times \text{Height}\\ {\text{D}}^2=12,800,000\times 36\\ \text{D=}\sqrt{12,800,000\times 36}\\ D=21.466\text{ km}\\ \boxed{D=20\text{ km}}\end{array}$

Therefore, the answer is $20\text{ km}$ .