CHAPTER 9 : SOME APPLICATIONS OF TRIGONOMETRY

CBSE Class 10 Mathematics — Previous Year Questions 2026

BASIC 2026
I. Multiple Choice Questions — [1 Mark each]
Type: Identifying Angles (Depression)
Question: In the given figure, which of the following angles represents the angle of depression?

Figure shows an observer at the top of a tower looking down at an object. Angles marked are \(x\) at the object, \(y\) between the tower and line of sight, and \(z\) between the horizontal line and line of sight.
(A) \(x\)    (B) \(y\)    (C) \(z\)    (D) \(a\)
Sets 430/1/1 (Q.12)
430/1/2 (Q.6)
430/1/3 (Q.17)
Type: Shadow Length Dynamics
Question: The length of the shadow of a tower when the sun's altitude changes from \(30^\circ\) to \(60^\circ\) will:
(A) become shorter    (B) become longer    (C) remain same    (D) be doubled
Sets 430/2/1 (Q.12)
430/2/2 (Q.6)
430/2/3 (Q.17)
Type: Calculating Angle of Elevation from Figure
Question: In the given figure, the angle of elevation of point \(A\) from point \(C\) is:

Figure shows a right-angled triangle \(ABC\), with \(AB = 2\) cm and \(BC = 2\sqrt{3}\) cm.
(A) \(30^\circ\)    (B) \(45^\circ\)    (C) \(60^\circ\)    (D) Cannot be determined
Sets 430/3/1 (Q.12)
430/3/2 (Q.6)
430/3/3 (Q.17)
II. Very Short Answer Questions — [2 Marks each]
Type: Pole and Tower Shadow Comparison
Question: A vertical pole of height \(10\) m casts a shadow of \(15\) m on the ground and at the same time, a tower casts a shadow of \(45\) m on the ground. Find the height of the tower.
Sets 430/3/1 (Q.22a)
430/3/2 (Q.25a)
430/3/3 (Q.23a)
III. Case Study Questions — [4 Marks each]
Case Study 1: Fireman and the Injured Bird
An injured bird is on a building \(15\) m high. A fireman uses an adjustable ladder making an angle of \(60^\circ\) with the ground to reach the roof.
(i) [1 Mark] Find the length of the ladder used to reach the roof.
(ii) [1 Mark] Find the distance of the point on the ground where the ladder was placed from the foot of the building.
(iii) [2 Marks] (a) If the fireman places the ladder against the opposite wall of the road making an angle of \(30^\circ\) with the ground to prevent slipping, find the width of the road.
OR
(b) Find the length of the ladder used in this new position.
Sets 430/1/1 (Q.36)
430/1/2 (Q.38)
Case Study 2: Kite Festival — Reena and Ravi
Reena's kite is flying at \(60\) m height with string tied to the ground at \(30^\circ\). Ravi is flying a kite at \(60\) m height from a \(10\) m high building. Both use the same length of string. \(\theta\) is the angle of elevation of Ravi's kite from the rooftop.
(i) [1 Mark] Find the length of string used by Reena.
(ii) [1 Mark] Find the value of \(\sin\theta\).
(iii) [2 Marks] (a) If \(\theta\) changes to \(60^\circ\) without changing string length, find the height of Ravi's kite above the ground. Use \(\sqrt{3}=1.7\).
OR
(b) What would be the height of Ravi's kite if the string had an inclination of \(30^\circ\)?
Sets 430/2/1 (Q.36)
430/2/2 (Q.38)
430/2/3 (Q.37)
STANDARD 2026
1. Multiple Choice Questions — [1 Mark]
Type: Finding Heights and Distances — Pole and Wire
Question: A wire is attached from a point \(A\) on the ground to the top of a pole \(BC\), making an angle of elevation as \(60^\circ\). If \(AB=5\sqrt{3}\) m, then length of the wire is:
(A) \(10\) m    (B) \(10\sqrt{3}\) m    (C) \(15\) m    (D) \(\frac{5}{2}\sqrt{3}\) m
Sets 30/5/1 (Q.17)
30/5/2 (Q.10)
30/5/3 (Q.8)
Type: Tower Elevation — Set 1
Question: A car is moving away from the base of a \(30\) m high tower. The angle of elevation of the top of the tower from the car at an instant, when the car is \(10\sqrt{3}\) m away from the base, is:
(A) \(30^\circ\)    (B) \(45^\circ\)    (C) \(90^\circ\)    (D) \(60^\circ\)
Sets 30/1/1 (Q.11)
30/1/2 (Q.12)
Type: Tower Height — Set 2
Question: From a point on the ground, which is \(60\) m away from the foot of a vertical tower, the angle of elevation of the top of the tower is found to be \(45^\circ\). The height (in metres) of the tower is:
(A) \(10\sqrt{3}\)    (B) \(30\sqrt{3}\)    (C) \(60\)    (D) \(30\)
Sets 30/2/1 (Q.12)
30/2/2 (Q.16)
30/2/3 (Q.7)
Type: Shadow and Sun's Altitude
Question: If the length of the shadow of a tower is \(\sqrt{3}\) times its height, then the sun's altitude is:
(A) \(45^\circ\)    (B) \(30^\circ\)    (C) \(60^\circ\)    (D) \(15^\circ\)
Set 30/3/1 (Q.9)
2. Long Answer Type — [5 Marks]
Type: Kite and Building Observations — Double Observation
Question: A kite is flying at a height of \(60\) m above the ground level. Ravi, standing at the roof of the house is holding the string straight and observes the angle of elevation of kite as \(30^\circ\). From the bottom of the same building, the angle of elevation of kite is \(45^\circ\). Find the length of the string and height of roof from the ground.

Use \(\sqrt{3}=1.73\).
Sets 30/4/1 (Q.34)
30/4/2 (Q.32)
30/4/3 (Q.32)
Type: Opposite Sides Observation
Question: A boy standing on a horizontal plane is flying a kite with a string of length \(60\) m, at an angle of elevation of \(30^\circ\). Another boy standing on the roof of a \(20\) m high building finds the angle of elevation of the same kite to be \(45^\circ\). If both the boys are on opposite sides of the kite, find the distance of the first boy from the base of the building. Also, find the height of the kite from the ground.

Use \(\sqrt{3}=1.73\).
Sets 30/1/1 (Q.35)
30/3/1 (Q.35)
Type: Tower and Flagstaff — Flagstaff Wires
Question: A vertical tower stands on a horizontal plane and is surmounted by a vertical flagstaff. From a point on the ground \(30\) m away from the tower, wires are attached to the top and bottom of the flagstaff making angles of elevation \(60^\circ\) and \(30^\circ\) respectively. Find the height of the tower and lengths of the wires attached.

Take \(\sqrt{3}=1.73\).
Set 30/3/2 (Q.32)
3. Case Study Questions — [4 Marks]
Case Study 1: The Elevated Water Tank
The building is \(54\) metres away from the water tank. From a window \(W\) of the building, the angle of elevation of the top of the tank is \(45^\circ\) and angle of depression of its foot is \(30^\circ\).
(i) [1 Mark] Write a relation between \(d\), the height of window, and \(y\).
(ii) [1 Mark] Determine the value of \(h\).
(iii) [2 Marks] (a) Determine the height of the water tank.
OR
(b) Find the value of \(x\) and height of the window above ground level.
Sets 30/5/1 (Q.38)
30/5/2 (Q.36)
30/5/3 (Q.36)
Case Study 2: The Radio Station Tower
A radio station tower was built in two sections \(A\) and \(B\). The tower is supported by wires from a point \(O\), \(6\) m away from the base. The angle of elevation of the top of section \(B\) is \(30^\circ\) and the angle of elevation of the top of section \(A\) is \(60^\circ\).
(i) [1 Mark] Find the length of the wire from point \(O\) to the top of section \(B\).
(ii) [1 Mark] Find the length of the wire from point \(O\) to the top of section \(A\).
(iii) [2 Marks] (a) Find the distance \(AB\).
OR
(b) Find the area of \(\triangle OPB\).
Set 30/1/1 (Q.37)
Case Study 3: Tejas and the Approaching Car
Tejas is standing at the top of a building and observes a car at an angle of depression of \(30^\circ\) as it approaches the base of the building at a uniform speed. \(6\) seconds later, the angle of depression increases to \(60^\circ\), and at that moment, the car is \(25\) m away from the building.
(i) [1 Mark] What is the height of the building?
(ii) [1 Mark] What is the distance between the two positions of the car?
(iii) [2 Marks] (a) What would be the total time taken by the car to reach the foot of the building from the starting point?
OR
(b) What is the distance of the observer from the car when it makes an angle of \(60^\circ\)?
Sets 30/2/1 (Q.37)
30/2/2 (Q.36)
30/2/3 (Q.38)
CBSE Class 10 Mathematics — Chapter 9 PYQ Collection
Basic + Standard Mathematics | 2026