Home
Class 12
MATHS
A man standing 30ms South of a tower of ...

A man standing 30ms South of a tower of height h walks 60 m to the East and finds the angle of elevation of the top of the tower to `30^(@)`. Find h.

Text Solution

AI Generated Solution

The correct Answer is:
To solve the problem step by step, we will follow these instructions: ### Step 1: Understand the Problem A man is standing 30 meters south of a tower of height \( h \). He walks 60 meters east and finds the angle of elevation to the top of the tower is \( 30^\circ \). We need to find the height \( h \) of the tower. ### Step 2: Draw a Diagram 1. Draw a vertical line representing the tower, labeled as \( OA \) where \( O \) is the base and \( A \) is the top of the tower. 2. Mark point \( B \) 30 meters south of point \( O \). 3. From point \( B \), draw a line 60 meters to the east to point \( C \). 4. The angle of elevation from point \( C \) to point \( A \) is \( 30^\circ \). ### Step 3: Identify the Triangle In triangle \( ABC \): - \( AB \) is the height of the tower \( h \). - \( BC \) is the distance walked east, which is 60 m. - \( OA \) is the height of the tower \( h \). - \( OB \) is the distance south, which is 30 m. ### Step 4: Calculate the Length of \( AC \) Using the Pythagorean theorem in triangle \( ABC \): \[ AC^2 = AB^2 + BC^2 \] Substituting the known values: \[ AC^2 = h^2 + 60^2 \] \[ AC^2 = h^2 + 3600 \] ### Step 5: Find the Length of \( AC \) Using the Angle of Elevation From point \( C \), the angle of elevation to the top of the tower is \( 30^\circ \). We can use the tangent function: \[ \tan(30^\circ) = \frac{h}{AC} \] Since \( \tan(30^\circ) = \frac{1}{\sqrt{3}} \): \[ \frac{1}{\sqrt{3}} = \frac{h}{AC} \] This implies: \[ h = AC \cdot \frac{1}{\sqrt{3}} \] ### Step 6: Calculate \( AC \) To find \( AC \), we can use the coordinates: - The horizontal distance from \( O \) to \( C \) is \( 60 \) m (east) and the vertical distance from \( O \) to \( B \) is \( 30 \) m (south). Using the Pythagorean theorem: \[ AC = \sqrt{(60)^2 + (30)^2} = \sqrt{3600 + 900} = \sqrt{4500} = 30\sqrt{5} \] ### Step 7: Substitute \( AC \) back into the height equation Now substitute \( AC \) into the height equation: \[ h = 30\sqrt{5} \cdot \frac{1}{\sqrt{3}} = 30 \cdot \frac{\sqrt{5}}{\sqrt{3}} = 10 \cdot \sqrt{15} \] ### Final Answer Thus, the height \( h \) of the tower is: \[ h = 10\sqrt{15} \text{ meters} \]
Promotional Banner

Similar Questions

Explore conceptually related problems

The angle of elevation of the top of a tower from the foot of a house, situated at a distance of 20 m from the tower is 60^(@) . From the top of the top of the house the angle of elevation of the top of the tower os 45^(@) . Find the height of house and tower.

A flag-staff stands on the top of a 5 m high tower. From a point on the ground, the angle of elevation of the top of the flag-staff is 60^@ and from the same point, the angle of elevation of the top of the tower is 45^@ . Find the height of the flag-staff.

A vertical tower is 20 m high. A man standing at some distance from the tower knows that the cosine of the angle of elevation of the top of the tower is 0.53. How far is he standing from the foot of the tower ?

Two people standing on the same side of a tower in a straight line with it, measure the angles of elevation of the top of the tower as 25^(@) and 50^(@) respectively. If the height of the tower is 70 m, find the distance between the two people

A person observed the angle of elevation of the top of a tower as 30^@ . He walked 50m 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.

From the top of a building 15m high the angle of elevation of the top of tower is found to be 30^@ . From the bottom of same building ; the angle of elevation of the top of the tower is found to be 60^@ . Find the height of the tower and the distance between tower and building .

A T.V. Tower stands vertically on a bank of a river. From a point on the other bank directly opposite to the tower, the angle of elevation of the top of the tower is 60 degrees. From a point 20m away this point on the same bank, the angle of elevation of the top of the tower is 30o . Find the height of the tower and the width of the river.

The persons are standing on the opposite sides of a tower. They observe the angles of elevation of the top of the tower to be 30^(@) and 38^(@) respectively. Find the distance between them, if the height of the tower is 50 m

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.

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.