Chapter 8, Problem 10RP

To determine

To calculate:The height of telephone pole.

Answer to Problem 10RP

The height of telephone pole is 20 m

Explanation of Solution

Given information:

A radio antenna of height 100 m casts a shadow of 80 m and shadow of a nearby pole is given as 10 m.

Formula used:

Comparing the ratios of height of pole to shadow of pole

Calculation :

  $\begin{array}{l}\frac{{\text{H}}_{\text{R}}\text{(height of radio antena)}}{S_{\text{R}}\text{(shadow of radio antena)}}=\frac{h_{\text{R}}\text{(height of telephone pole)}}{s_{\text{R}}\text{(shadow of telephone pole)}}\\ \Rightarrow \frac{100}{80}=\frac{h_R}{16}\\ \Rightarrow h_R=16\times \frac{100}{80}=20m\end{array}$