An electrician 7

An electrician has to repair an electric fault on a pole 4 meters in height. He needs to reach a point 1 m below the top. What should be the length of the ladder that he could use, when inclined at an angle 60° to the horizontal?

Final Answer:

x =  3.4641 m

Step-by-step explanation:

$$\begin{gathered} a=4\text{m} \\ b=1\text{m} \\ \alpha =60{}^{\circ } \\ c=a-b=4-1=3\text{m} \\ \sin \alpha =c:x \\ x=\frac{c}{\sin \alpha }=\frac{c}{\sin 60°}=\frac{3}{\sin 60°}=\frac{3}{0.866025}=3.464=3.4641\text{m} \end{gathered}$$

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