Last updated at May 29, 2018 by Teachoo

Transcript

Example 1 A tower stands vertically on the ground. From a point on the ground, which is 15 m away from the foot of the tower, the angle of elevation of the top of the tower is found to be 60°. Find the height of the tower. Let, the height of the tower be H meter. So, AB = H metre Distance of the point from the foot of the tower = 15m Hence, CB = 15m Angle of elevation = 60° ∠ACB = 60° Since tower is vertical to ground, So, ∠ ABC = 90° Now, tan C = (𝑆𝑖𝑑𝑒 𝑜𝑝𝑝𝑜𝑠𝑖𝑡𝑒 𝑡𝑜 𝑎𝑛𝑔𝑙𝑒" c " )/(𝑆𝑖𝑑𝑒 𝑎𝑑𝑗𝑎𝑐𝑒𝑛𝑡 𝑡𝑜 𝑎𝑛𝑔𝑙𝑒" " 𝐶) tan C = (" " 𝐴𝐵)/𝐶𝐵 tan 60° = 𝐴𝐵/𝐶𝐵 √3 = 𝐻/15 15√3 = H H = 15√3 Hence, height of the tower = H = 15√3 m

Questions easy to difficult

Angle of Elevation and Angle of Depression

Angle of Depression from point A to point B is same as Angle of Elevation from point B to point A

How to find Height when angle of elevation is given?

How to find Distance when angle of depression is given?

Example 1 You are here

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About the Author

Davneet Singh

Davneet Singh is a graduate from Indian Institute of Technology, Kanpur. He has been teaching from the past 10 years. He provides courses for Maths and Science at Teachoo.