Last updated at Dec. 24, 2019 by Teachoo

Transcript

Ex 9.1 , 2 A tree breaks due to storm and the broken part bends so that the top of the tree touches the ground making an angle 30° with it. The distance between the foot of the tree to the point where the top touches the ground is 8 m. Find the height of the tree. Let, the broken part of tree be AC It is given that, Distance between foot of the tree B and point C = 8m So, BC = 8m Also, broken parts of tree makes an angle 30° with ground So, ∠C = 30° We need to find height of tree Height of tree = Height of broken part + height of remaining tree Height of tree = AB + AC Since, Tree was vertical to ground So, ∠ ABC = 90° So, Height of tree = AC + AB = 16/√3 + 8/√3 = 24/√3 Multiplying √3 in numerator and denominator = 24/√3 × √3/√3 = 24 × √3/3 = 8√3 Hence, height of tree is 8√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

EX 9.1, 4

EX 9.1, 5

EX 9.1, 3 Important

EX 9.1, 2 Important You are here

Ex 9.1, 7

Example 4

Example 2 Important

EX 9.1, 8

Example 5 Important

Ex 9.1, 11 Important

Example 7 Important

Example 3 Important

Ex 9.1, 6 Important

EX 9.1, 9 Important

Ex 9.1, 10 Important

Example 6 Important

Ex 9.1, 13 Important

Ex 9.1, 12 Important

Ex 9.1, 16 Important

Ex 9.1, 14 Important

Ex 9.1, 15 Important

EX 9.1, 1

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.