Chapter CSB1.11, Problem 7E

To determine

The height of ladder.

Answer to Problem 7E

The height upto which ladder reach is $h=18.13\text{foot}$

Explanation of Solution

Given:

The given data is,

Ladder length, L = 20 foot, Angle with ground, $\theta ={65}^{\circ }$

From the given condition, the figure obtained is

  

The height upto which ladder reach is,

  $\begin{array}{l}\mathrm{Sin}\theta =\frac{\text{perpendicular}}{\text{hypetenuse}}=\frac{h}{L}\\ \Rightarrow \mathrm{Sin}{65}^{\circ }=\frac{h}{20}\\ \Rightarrow h=18.13\text{foot}\end{array}$