Tips And Tricks And Shortcuts To Solve Height And Distance

Shortcuts and Easy Tips & Tricks to solve questions

• How to solve word problems that involve angle of elevation or depression.

Step 1: Draw a sketch of the situation given.
Step 2: Mark in the given angle of elevation or depression and other information.
Step 3: Use trigonometry to find the required missing length

Learn the values of these trigonometric ratios.

 Type 1: Find the distance/height/base/length when angle is given

Question 1.

A boy is flying a kite in the evening. The thread of the kite was 120 m long and the angle of elevation with the boy’s eyes was 30°. Find the height of the kite?
Options.
A. 30 m
B. 60 m
C. 40 m
D. 55 m

Solution:

Sin 30° = Perpendicular/Hypotenuse = AB/AC
1/2 = h/120
h = 60 m

Correct option: B

Type 2: Find the angle when distance/height/base/length is given

Question 2.

Find the angle of elevation of the sun when the shadow of a pole of 18 m height is 6√3 m long?

Options.
A. 45°
B. 60°
C. 30°
D. 90°

Solution:

Let AB be the pole and CB be the shadow
Given that AB = 18 m and CB = 6√3
Let the angle of elevation, ACB = θ
From the right ΔABC,
Tan θ = Perpendicular/Base = AB/BC = 18/6√3 = 3/√3 = √3
Therefore,
θ =tan^–¹(√3)=60°

Correct option: B