English

Prove the following: Find the angle of elevation of the sun when the shadow of a pole h metres high is 3 h metres long. - Mathematics

Advertisements
Advertisements

Question

Find the angle of elevation of the sun when the shadow of a pole h metres high is `sqrt(3)` h metres long.

Sum

Solution


Let the angle of elevation of the sun is θ.

Given, height of pole = h m

Now, In ∆ABC,

tan θ = `"AC"/"BC" = "h"/(sqrt(3)"h")`

⇒ tan θ = `1/sqrt(3)`

⇒ tan 30°

⇒ θ = 30°

Hence, the angle of elevation of the sun is 30°.

shaalaa.com
  Is there an error in this question or solution?
Chapter 8: Introduction To Trigonometry and Its Applications - Exercise 8.3 [Page 95]

APPEARS IN

NCERT Exemplar Mathematics [English] Class 10
Chapter 8 Introduction To Trigonometry and Its Applications
Exercise 8.3 | Q 8 | Page 95

RELATED QUESTIONS

A person standing on the bank of river observes that the angle of elevation of the top of a tree standing on the opposite bank is 60°. When he moves 40 m away from the bank, he finds the angle of elevation to be 30°. Find the height of the tree and width of the river. `(sqrt 3=1.73)`


Two stations due south of a leaning tower which leans towards the north are at distance a and b from its foot. If α, β be the elevations of the top of the tower from these stations, prove that its inclination θ to the horizontal is given by `\text{cot }\theta =\frac{bcot alpha -a\cot \beta }{b-a}`


The angle of elevation of the top of a tower from a point A due south of the tower is α and from B due east of the tower is β. If AB = d, show that the height of the tower is

`\frac{d}{\sqrt{\cot ^{2}\alpha +\cot^{2}\beta `


The angle of elevation of the top of a building from the foot of the tower is 30° and the angle of elevation of the top of the tower from the foot of the building is 60°. If the tower is 50 m high, find the height of the building.


A person observed the angle of elevation of the top of a tower as 30°. He walked 50 m towards the foot of the tower along level ground and found the angle of elevation of the top of the tower as 60°. Find the height of the tower.


The angle of elevation of the top of a tower at a distance of 120 m from a point A on the ground is 45 . If the angle of elevation of the top of a flagstaff fixed at the top of the tower, at A is 60 , then find the height of the flagstaff [Use `sqrt(3)` 1.732]


As observed form the top of a lighthouse, 100m above sea level, the angle of depression of a ship, sailing directly towards it, changes from 30° and 60° . Determine the distance travelled by the ship during the period of observation.


A tree is broken by the wind. The top struck the ground at an angle of 30° and at a distance 30 m from the root. Find the whole height of the tree. (`sqrt(3)`=1.73)


A plane is observed to be approaching the airport. It is at a distance of 12 km from the point of observation and makes an angle of elevation of 60°. The height above the ground of the plane is ____________.


The angles of elevation of the top of the rock from the top and foot of 100 m high tower are respectively 30° and 45°. The height of the rock is ____________.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×