The diagram below shows the position of a ferry with respect to the lighthouse and $AC=100$ m, \(\

Question

The diagram below shows the position of a ferry with respect to the lighthouse and $AC=100$ m, $\angle ACB=25{}^\circ$, $BD=\frac{1}{2}BC$. Calculate the distance, $BC$, of the ferry to the base of the lighthouse. Calculate the height, $AB$, of the lighthouse. If the ferry is at $D$, calculate the angle of elevation, $y{}^\circ $, from the ferry to the top of the lighthouse.

Accepted Answer

(i) $BC=90.6\text{ m}\text{ (3 s.f.)}$ (ii) $AB=42.3\text{ m}\text{ (3 s.f.)}$ (iii) $y=43.0^\circ\text{ (1 d.p.)}$

The Lighthouse Problem: Calculating Heights and Elevation

The Lighthouse Problem: Calculating Heights and Elevation

Video Solution:

Solution:

Solution locked