Question

An electrician wants to repair an electric connection on a pole of height 9m. He needs to reach 1.8 m below the top of the pole to do work. What should be the length of the ladder which he should use, when he climbs it an angle 60 with the ground?what will be the the distance between foot of the ladder and foot of the pole?

Answer 1

Answer:

Step-by-step explanation:

Answer 2

Answer:

The length of the ladder  is 8.313 m and he distance between foot of the ladder and foot of the pole is 4.156

Step-by-step explanation:

Refer the attached figure

Length of pole = AC = 9 m

He needs to reach 1.8 m below the top of the pole i.e. AB = 1.8 m

BC = AC-AB = 9-1.8 = 7.2 m

Length of ladder is CD

Now in ΔBCD

$Sin \theta = \frac{perpendicular}{hypotenuse}$

$Sin 60 = \frac{CB}{CD}$

$\frac{\sqrt{3}}{2} = \frac{7.2}{CD}$

$CD = 8.313$

Again in ΔBCD

$tan \theta = \frac{perpendicular}{Base}$

$tan 60 = \frac{CB}{BC}$

$\sqrt{3} = \frac{7.2}{BC}$

$BC= \frac{7.2}{\sqrt{3}}$

$BC= 4.156$

Hence the length of the ladder  is 8.313 m and he distance between foot of the ladder and foot of the pole is 4.156