Mathematics · Textbook solutions
Some Applications of Trigonometry
Every solved example, exercise, and miscellaneous question, in the order the textbook teaches them. Plus every board question asked from this chapter. · 22 questions
9.1 Heights and Distances
22 q
Solved Examples
Worked · 7
- 9.1 Eg.1A 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 . Find the height of the tower.
- 9.1 Eg.2An electrician has to repair an electric fault on a pole of height 5 m. She needs to reach a point 1.3 m below the top of the pole to undertake the repair work. What should be the length of the ladder that she should use which, when inclined at an angle of to the horizontal, would enable her to reach the required position? Also, how far from the foot of the pole should she place the foot of the ladder? (You may take )
- 9.1 Eg.3An observer 1.5 m tall is 28.5 m away from a chimney. The angle of elevation of the top of the chimney from her eyes is . What is the height of the chimney?
- 9.1 Eg.4From a point P on the ground the angle of elevation of the top of a 10 m tall building is . A flag is hoisted at the top of the building and the angle of elevation of the top of the flagstaff from P is . Find the length of the flagstaff and the distance of the building from the point P. (You may take )
- 9.1 Eg.5The shadow of a tower standing on a level ground is found to be 40 m longer when the Sun’s altitude is than when it is . Find the height of the tower.
- 9.1 Eg.6The angles of depression of the top and the bottom of an 8 m tall building from the top of a multi-storeyed building are and , respectively. Find the height of the multi-storeyed building and the distance between the two buildings.
- 9.1 Eg.7From a point on a bridge across a river, the angles of depression of the banks on opposite sides of the river are and , respectively. If the bridge is at a height of 3 m from the banks, find the width of the river.
Exercise 9.1
Practice · 15
- Ex 9.1 Q1A circus artist is climbing a 20 m long rope, which is tightly stretched and tied from the top of a vertical pole to the ground. Find the height of the pole, if the angle made by the rope with the ground level is (see Fig. 9.11).
- Ex 9.1 Q2A tree breaks due to storm and the broken part bends so that the top of the tree touches the ground making an angle 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.
- Ex 9.1 Q3A contractor plans to install two slides for the children to play in a park. For the children below the age of 5 years, she prefers to have a slide whose top is at a height of 1.5 m, and is inclined at an angle of to the ground, whereas for elder children, she wants to have a steep slide at a height of 3 m, and inclined at an angle of to the ground. What should be the length of the slide in each case?
- Ex 9.1 Q4The angle of elevation of the top of a tower from a point on the ground, which is 30 m away from the foot of the tower, is . Find the height of the tower.
- Ex 9.1 Q5A kite is flying at a height of 60 m above the ground. The string attached to the kite is temporarily tied to a point on the ground. The inclination of the string with the ground is . Find the length of the string, assuming that there is no slack in the string.
- Ex 9.1 Q6A 1.5 m tall boy is standing at some distance from a 30 m tall building. The angle of elevation from his eyes to the top of the building increases from to as he walks towards the building. Find the distance he walked towards the building.
- Ex 9.1 Q7From a point on the ground, the angles of elevation of the bottom and the top of a transmission tower fixed at the top of a 20 m high building are and respectively. Find the height of the tower.
- Ex 9.1 Q8A statue, 1.6 m tall, stands on the top of a pedestal. From a point on the ground, the angle of elevation of the top of the statue is and from the same point the angle of elevation of the top of the pedestal is . Find the height of the pedestal.
- Ex 9.1 Q9The angle of elevation of the top of a building from the foot of the tower is and the angle of elevation of the top of the tower from the foot of the building is . If the tower is 50 m high, find the height of the building.
- Ex 9.1 Q10Two poles of equal heights are standing opposite each other on either side of the road, which is 80 m wide. From a point between them on the road, the angles of elevation of the top of the poles are and , respectively. Find the height of the poles and the distances of the point from the poles.
- Ex 9.1 Q11A TV tower stands vertically on a bank of a canal. From a point on the other bank directly opposite the tower, the angle of elevation of the top of the tower is . From another point 20 m away from this point on the line joining this point to the foot of the tower, the angle of elevation of the top of the tower is (see Fig. 9.12). Find the height of the tower and the width of the canal.
- Ex 9.1 Q12From the top of a 7 m high building, the angle of elevation of the top of a cable tower is and the angle of depression of its foot is . Determine the height of the tower.
- Ex 9.1 Q13As observed from the top of a 75 m high lighthouse from the sea-level, the angles of depression of two ships are and . If one ship is exactly behind the other on the same side of the lighthouse, find the distance between the two ships.
- Ex 9.1 Q14A 1.2 m tall girl spots a balloon moving with the wind in a horizontal line at a height of 88.2 m from the ground. The angle of elevation of the balloon from the eyes of the girl at any instant is . After some time, the angle of elevation reduces to (see Fig. 9.13). Find the distance travelled by the balloon during the interval.
- Ex 9.1 Q15A straight highway leads to the foot of a tower. A man standing at the top of the tower observes a car at an angle of depression of , which is approaching the foot of the tower with a uniform speed. Six seconds later, the angle of depression of the car is found to be . Find the time taken by the car to reach the foot of the tower from this point.
What the board has asked from this chapter
Questions per paper · 67 papers · 2022 to 2026
2022: 2.8 questions per paper. 2023: 1.4 questions per paper. 2024: 1.1 questions per paper. 2025: 1.7 questions per paper. 2026: 1.5 questions per paper
2026
22 q
- 9The string of a flying kite is tied to a point on the ground. The length of the string between the kite and the point on the ground is 80 m. The string makes an angle of with the ground. The height of the kite above the ground is :
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Angle of Elevation Problems - 9If the length of the shadow of a tower is times that of its height, then altitude of the Sun is :
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Angle of Elevation Problems - 11A 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 m away from the base of the tower, is :
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Angle of Elevation Problems - 12From 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 . The height (in metres) of the tower is :
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Angle of Elevation Problems - 17A wire is attached from a point A on the ground to the top of a pole BC, making an angle of elevation as . If m, then length of the wire is
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Angle of Elevation Problems - 32A 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 and respectively. Find the height of the tower and lengths of the wires attached. (Take )Angle of Elevation Problems
- 34 (a)The angle of elevation of the top of a building from a point A, on the ground, is . On moving a distance of 24 m towards its base to the point B, the angle of elevation changes to . Find the height of the building and distance of point A from the base of the building. (Take )Angle of Elevation Problems
- 34A 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 . From the bottom of the same building, the angle of elevation of kite is . Find the length of the string and height of roof from the ground. (Use )Angle of Elevation Problems
- 34 (b)A tower stands vertically on the ground. A man standing at the top of the tower observes his friend at an angle of depression of , who is approaching the foot of the tower with a uniform speed. 30 seconds later, the angle of depression changes to . Find the time taken by his friend to reach the foot of the tower from this point.Angle of Depression Problems
- 35A boy standing on a horizontal plane is flying a kite with a string of length 60 m, at an angle of elevation of . Another boy standing on the roof of a 20 m high building, finds the angle of elevation of same kite to be . 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 )Angle of Elevation Problems
- Tejas is standing at the top of a building and observes a car at an angle of depression of as it approaches the base of the building at a uniform speed. 6 seconds later, the angle of depression increases to , and at that moment, the car is 25 m away from the building. Based on the information given above, answer the following questions :37 (i)What is the height of the building ?Angle of Depression Problems
- Radio towers are used for transmitting a range of communication services including radio and television. The tower will either act as an antenna itself or support one or more antennas on its structure. On a similar concept, a radio station tower was built in two sections ‘A’ and ‘B’. Tower is supported by wires from a point ‘O’ (as shown in figure). Distance between the base of the tower and point ‘O’ is 6 m. From point ‘O’, the angle of elevation of the top of the section ‘B’ is and the angle of elevation of the top of section ‘A’ is . Based on the above information, answer the following questions :37 (i)Find the length of the wire from the point ‘O’ to the top of section ‘B’.Angle of Elevation Problems
- Tejas is standing at the top of a building and observes a car at an angle of depression of as it approaches the base of the building at a uniform speed. 6 seconds later, the angle of depression increases to , and at that moment, the car is 25 m away from the building. Based on the information given above, answer the following questions :37 (ii)What is the distance between the two positions of the car ?Angle of Depression Problems
- Radio towers are used for transmitting a range of communication services including radio and television. The tower will either act as an antenna itself or support one or more antennas on its structure. On a similar concept, a radio station tower was built in two sections ‘A’ and ‘B’. Tower is supported by wires from a point ‘O’ (as shown in figure). Distance between the base of the tower and point ‘O’ is 6 m. From point ‘O’, the angle of elevation of the top of the section ‘B’ is and the angle of elevation of the top of section ‘A’ is . Based on the above information, answer the following questions :37 (ii)Find the length of the wire from the point ‘O’ to the top of section ‘A’.Angle of Elevation Problems
- Tejas is standing at the top of a building and observes a car at an angle of depression of as it approaches the base of the building at a uniform speed. 6 seconds later, the angle of depression increases to , and at that moment, the car is 25 m away from the building. Based on the information given above, answer the following questions :37 (iii) (a)What would be the total time taken by the car to reach the foot of the building from the starting point ?Angle of Depression Problems
- Radio towers are used for transmitting a range of communication services including radio and television. The tower will either act as an antenna itself or support one or more antennas on its structure. On a similar concept, a radio station tower was built in two sections ‘A’ and ‘B’. Tower is supported by wires from a point ‘O’ (as shown in figure). Distance between the base of the tower and point ‘O’ is 6 m. From point ‘O’, the angle of elevation of the top of the section ‘B’ is and the angle of elevation of the top of section ‘A’ is . Based on the above information, answer the following questions :37 (iii) (a)Find the distance AB.Angle of Elevation Problems
- Tejas is standing at the top of a building and observes a car at an angle of depression of as it approaches the base of the building at a uniform speed. 6 seconds later, the angle of depression increases to , and at that moment, the car is 25 m away from the building. Based on the information given above, answer the following questions :37 (iii) (b)What is the distance of the observer from the car when it makes an angle of ?Angle of Depression Problems
- Radio towers are used for transmitting a range of communication services including radio and television. The tower will either act as an antenna itself or support one or more antennas on its structure. On a similar concept, a radio station tower was built in two sections ‘A’ and ‘B’. Tower is supported by wires from a point ‘O’ (as shown in figure). Distance between the base of the tower and point ‘O’ is 6 m. From point ‘O’, the angle of elevation of the top of the section ‘B’ is and the angle of elevation of the top of section ‘A’ is . Based on the above information, answer the following questions :37 (iii) (b)Find the area of .Angle of Elevation Problems
- Elevated water storage tanks are built to store and supply water to nearby colonies. In the diagram given above, AB is an elevated water tank and CD is a nearby multistorey building. The building is 54 metres away from the water tank. From a window (W) of the building, the angle of elevation of top of the tank is and angle of depression of its foot is .38 (i)Write a relation between d (the height of window) and y.Angle of Depression Problems
- Elevated water storage tanks are built to store and supply water to nearby colonies. In the diagram given above, AB is an elevated water tank and CD is a nearby multistorey building. The building is 54 metres away from the water tank. From a window (W) of the building, the angle of elevation of top of the tank is and angle of depression of its foot is .38 (ii)Determine the value of h.Angle of Elevation Problems
- Elevated water storage tanks are built to store and supply water to nearby colonies. In the diagram given above, AB is an elevated water tank and CD is a nearby multistorey building. The building is 54 metres away from the water tank. From a window (W) of the building, the angle of elevation of top of the tank is and angle of depression of its foot is .38 (iii) (a)Determine height of the water tank.Angle of Elevation Problems
- Elevated water storage tanks are built to store and supply water to nearby colonies. In the diagram given above, AB is an elevated water tank and CD is a nearby multistorey building. The building is 54 metres away from the water tank. From a window (W) of the building, the angle of elevation of top of the tank is and angle of depression of its foot is .38 (iii) (b)Find the value of and height of the window above ground level.Angle of Elevation Problems
2025
30 q
- 10A 30 m long rope is tightly stretched and tied from the top of pole to the ground. If the rope makes an angle of with the ground, the height of the pole is :
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Angle of Elevation Problems - 13A peacock sitting on the top of a tree of height 10 m observes a snake moving on the ground. If the snake is m away from the base of the tree, then angle of depression of the snake from the eye of the peacock is
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Angle of Depression Problems - 13An observer 1.8 m tall stands away from a chimney at a distance of 38.2 m along the ground. The angle of elevation of top of chimney from the eyes of observer is . The height of chimney above the ground is
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Angle of Elevation Problems - 15A ladder 14 m long leans against a wall. If the foot of the ladder is 7 m from the wall, then the angle of elevation of the top of the wall is :
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Angle of Elevation Problems - 17A kite is flying at a height of 150 m from the ground. It is attached to a string inclined at an angle of to the horizontal. The length of the string is :
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Angle of Elevation Problems - Questions number 19 and 20 are Assertion and Reason based questions. Two statements are given, one labelled as Assertion (A) and the other is labelled as Reason (R). Select the correct answer to these questions from the codes (A), (B), (C) and (D) as given below.19Assertion (A) : A ladder leaning against a wall, stands at a horizontal distance of 6 m from the wall. If the height of the wall up to which the ladder reaches is 8 m, then the length of the ladder is 10 m. Reason (R) : The ladder makes an angle of with the ground.
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Angle of Elevation Problems - 32 (a)Two ships are sailing in the sea on either side of a lighthouse. The angles of depression to the two ships as observed from the top of the lighthouse are and , respectively. If the distance between the ships is m, then find the height of the lighthouse.Angle of Depression Problems
- 32 (b)The angles of depression of the top and the bottom of an 8 m tall building from the top of another multistoried building are and , respectively. Find the height of the multistoried building and the distance between the two buildings.Angle of Depression Problems
- 35 (a)The angle of elevation of an airborne helicopter from a point A on the ground is . After a flight of 15 seconds, the angle of elevation of the helicopter changes to . If the helicopter is flying at a constant height of 2000 m, find the speed of the helicopter. (Take )Angle of Elevation Problems
- 35 (b)A girl m tall is standing at some distance from a 30 m high tower. The angle of elevation from her eye to the top of the tower increases from to as she walks towards the tower. Find the distance she walked towards the tower.Angle of Elevation Problems
- A lighthouse stands tall on a cliff by the sea, watching over ships that pass by. One day a ship is seen approaching the shore and from the top of the lighthouse, the angles of depression of the ship are observed to be and as it moves from point P to point Q. The height of the lighthouse is 50 metres. Based on the information given above, answer the following questions :37 (i)Find the distance of the ship from the base of the lighthouse when it is at point Q, where the angle of depression is .Angle of Depression Problems
- A lighthouse stands tall on a cliff by the sea, watching over ships that pass by. One day a ship is seen approaching the shore and from the top of the lighthouse, the angles of depression of the ship are observed to be and as it moves from point P to point Q. The height of the lighthouse is 50 metres. Based on the information given above, answer the following questions :37 (ii)Find the measures of and .Angle of Depression Problems
- A lighthouse stands tall on a cliff by the sea, watching over ships that pass by. One day a ship is seen approaching the shore and from the top of the lighthouse, the angles of depression of the ship are observed to be and as it moves from point P to point Q. The height of the lighthouse is 50 metres. Based on the information given above, answer the following questions :37 (iii) (a)Find the distance travelled by the ship between points P and Q.Angle of Depression Problems
- A lighthouse stands tall on a cliff by the sea, watching over ships that pass by. One day a ship is seen approaching the shore and from the top of the lighthouse, the angles of depression of the ship are observed to be and as it moves from point P to point Q. The height of the lighthouse is 50 metres. Based on the information given above, answer the following questions :37 (iii) (b)If the ship continues moving towards the shore and takes 10 minutes to travel from Q to A, calculate the speed of the ship in km/h, from Q to A.Angle of Depression Problems
- Amrita stood near the base of a lighthouse, gazing up at its towering height. She measured the angle of elevation to the top and found it to be . Then, she climbed a nearby observation deck, 40 metres higher than her original position and noticed the angle of elevation to the top of lighthouse to be . Based on the above given information, answer the following questions :38 (i)If CD is h metres, find the distance BD in terms of ‘h’.Angle of Elevation Problems
- A drone was used to facilitate movement of an ambulance on the straight highway to a point P on the ground where there was an accident. The ambulance was travelling at the speed of 60 km/h. The drone stopped at a point Q, 100 m vertically above the point P. The angle of depression of the ambulance was found to be at a particular instant. Based on above information, answer the following questions :38 (i)Represent the above situation with the help of a diagram.Angle of Depression Problems
- The Statue of Unity situated in Gujarat is the world’s largest Statue which stands over a 58 m high base. As part of the project, a student constructed an inclinometer and wishes to find the height of Statue of Unity using it. He noted following observations from two places : Situation – I : The angle of elevation of the top of Statue from Place A which is m away from the base of the Statue is found to be . Situation – II : The angle of elevation of the top of Statue from a Place B which is 40 m above the ground is found to be and entire height of the Statue including the base is found to be 240 m. Based on given information, answer the following questions :38 (i)Represent the Situation – I with the help of a diagram.Angle of Elevation Problems
- Passenger boarding stairs, sometimes referred to as boarding ramps, stair cars or aircraft steps, provide a mobile means to travel between the aircraft doors and the ground. Larger aircraft have door sills 5 to 20 feet (1 foot = 30 cm) high. Stairs facilitate safe boarding and de-boarding. An aircraft has a door sill at a height of 15 feet above the ground. A stair car is placed at a horizontal distance of 15 feet from the plane. Based on given information, answer the questions given in part (i) and (ii).38 (i)Find the angle at which stairs are inclined to reach the door sill 15 feet high above the ground.Angle of Elevation Problems
- A drone was used to facilitate movement of an ambulance on the straight highway to a point P on the ground where there was an accident. The ambulance was travelling at the speed of 60 km/h. The drone stopped at a point Q, 100 m vertically above the point P. The angle of depression of the ambulance was found to be at a particular instant. Based on above information, answer the following questions :38 (ii)Find the distance between the ambulance and the site of accident (P) at the particular instant. (Use )Angle of Depression Problems
- The Statue of Unity situated in Gujarat is the world’s largest Statue which stands over a 58 m high base. As part of the project, a student constructed an inclinometer and wishes to find the height of Statue of Unity using it. He noted following observations from two places : Situation – I : The angle of elevation of the top of Statue from Place A which is m away from the base of the Statue is found to be . Situation – II : The angle of elevation of the top of Statue from a Place B which is 40 m above the ground is found to be and entire height of the Statue including the base is found to be 240 m. Based on given information, answer the following questions :38 (ii)Represent the Situation – II with the help of a diagram.Angle of Elevation Problems
- Passenger boarding stairs, sometimes referred to as boarding ramps, stair cars or aircraft steps, provide a mobile means to travel between the aircraft doors and the ground. Larger aircraft have door sills 5 to 20 feet (1 foot = 30 cm) high. Stairs facilitate safe boarding and de-boarding. An aircraft has a door sill at a height of 15 feet above the ground. A stair car is placed at a horizontal distance of 15 feet from the plane. Based on given information, answer the questions given in part (i) and (ii).38 (ii)Find the length of stairs used to reach the door sill.Angle of Elevation Problems
- Amrita stood near the base of a lighthouse, gazing up at its towering height. She measured the angle of elevation to the top and found it to be . Then, she climbed a nearby observation deck, 40 metres higher than her original position and noticed the angle of elevation to the top of lighthouse to be . Based on the above given information, answer the following questions :38 (ii)Find distance BC in terms of ‘h’.Angle of Elevation Problems
- The Statue of Unity situated in Gujarat is the world’s largest Statue which stands over a 58 m high base. As part of the project, a student constructed an inclinometer and wishes to find the height of Statue of Unity using it. He noted following observations from two places : Situation – I : The angle of elevation of the top of Statue from Place A which is m away from the base of the Statue is found to be . Situation – II : The angle of elevation of the top of Statue from a Place B which is 40 m above the ground is found to be and entire height of the Statue including the base is found to be 240 m. Based on given information, answer the following questions :38 (iii) (a)Calculate the height of Statue excluding the base and also find the height including the base with the help of Situation – I.Angle of Elevation Problems
- Passenger boarding stairs, sometimes referred to as boarding ramps, stair cars or aircraft steps, provide a mobile means to travel between the aircraft doors and the ground. Larger aircraft have door sills 5 to 20 feet (1 foot = 30 cm) high. Stairs facilitate safe boarding and de-boarding. An aircraft has a door sill at a height of 15 feet above the ground. A stair car is placed at a horizontal distance of 15 feet from the plane. Based on given information, answer the questions given in part (i) and (ii).38 (iii) (a)If the 20 feet long stairs is inclined at an angle of to reach the door sill, then find the height of the door sill above the ground. (use )Angle of Elevation Problems
- Amrita stood near the base of a lighthouse, gazing up at its towering height. She measured the angle of elevation to the top and found it to be . Then, she climbed a nearby observation deck, 40 metres higher than her original position and noticed the angle of elevation to the top of lighthouse to be . Based on the above given information, answer the following questions :38 (iii) (a)Find the height CE of the lighthouse [Use ]Angle of Elevation Problems
- A drone was used to facilitate movement of an ambulance on the straight highway to a point P on the ground where there was an accident. The ambulance was travelling at the speed of 60 km/h. The drone stopped at a point Q, 100 m vertically above the point P. The angle of depression of the ambulance was found to be at a particular instant. Based on above information, answer the following questions :38 (iii) (a)Find the time (in seconds) in which the angle of depression changes from to .Angle of Depression Problems
- Amrita stood near the base of a lighthouse, gazing up at its towering height. She measured the angle of elevation to the top and found it to be . Then, she climbed a nearby observation deck, 40 metres higher than her original position and noticed the angle of elevation to the top of lighthouse to be . Based on the above given information, answer the following questions :38 (iii) (b)Find distance AE, if AC = 100 m.Angle of Elevation Problems
- The Statue of Unity situated in Gujarat is the world’s largest Statue which stands over a 58 m high base. As part of the project, a student constructed an inclinometer and wishes to find the height of Statue of Unity using it. He noted following observations from two places : Situation – I : The angle of elevation of the top of Statue from Place A which is m away from the base of the Statue is found to be . Situation – II : The angle of elevation of the top of Statue from a Place B which is 40 m above the ground is found to be and entire height of the Statue including the base is found to be 240 m. Based on given information, answer the following questions :38 (iii) (b)Find the horizontal distance of point B (Situation – II) from the Statue and the value of , where is the angle of elevation of top of base of the Statue from point B.Angle of Elevation Problems
- Passenger boarding stairs, sometimes referred to as boarding ramps, stair cars or aircraft steps, provide a mobile means to travel between the aircraft doors and the ground. Larger aircraft have door sills 5 to 20 feet (1 foot = 30 cm) high. Stairs facilitate safe boarding and de-boarding. An aircraft has a door sill at a height of 15 feet above the ground. A stair car is placed at a horizontal distance of 15 feet from the plane. Based on given information, answer the questions given in part (i) and (ii).38 (iii) (b)What should be the shortest possible length of stairs to reach the door sill of the plane 20 feet above the ground, if the angle of elevation cannot exceed ? Also, find the horizontal distance of base of stair car from the plane.Angle of Elevation Problems
- A drone was used to facilitate movement of an ambulance on the straight highway to a point P on the ground where there was an accident. The ambulance was travelling at the speed of 60 km/h. The drone stopped at a point Q, 100 m vertically above the point P. The angle of depression of the ambulance was found to be at a particular instant. Based on above information, answer the following questions :38 (iii) (b)How long (in seconds) will the ambulance take to reach point P from a point T on the highway such that angle of depression of the ambulance at T is from the drone ?Angle of Depression Problems
2024
17 q
- 7From a point on the ground, which is 30 m away from the foot of a vertical tower, the angle of elevation of the top of the tower is found to be . The height (in metres) of the tower is :
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Angle of Elevation Problems - 10The length of the shadow of a tower on the plane ground is times the height of the tower. The angle of elevation of the Sun is :
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Angle of Elevation Problems - 14At some time of the day, the length of the shadow of a tower is equal to its height. Then, the Sun’s altitude at that time is :
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Angle of Elevation Problems - 17The ratio of the length of a pole and its shadow on the ground is . The angle of elevation of the Sun is :
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Angle of Elevation Problems - 32The angle of elevation of an aircraft from a point A on the ground is . After a flight of 30 seconds, the angle of elevation changes to . The aircraft is flying at a constant height of m at a uniform speed. Find the speed of the aircraft.Angle of Elevation Problems
- 32A person standing on the bank of a river observes that the angle of elevation of the top of a tower on the opposite bank is . When he moves 30 m away from the bank, he finds the angle of elevation to be . Find the height of the tower and width of the river. (Take )Angle of Elevation Problems
- 32Two pillars of equal lengths stand on either side of a road which is 100 m wide, exactly opposite to each other. At a point on the road between the pillars, the angles of elevation of the tops of the pillars are and . Find the length of each pillar and distance of the point on the road from the pillars. (Use )Angle of Elevation Problems
- 32From the top of a 15 m high building, the angle of elevation of the top of a tower is found to be . From the bottom of the same building, the angle of elevation of the top of the tower is found to be . Find the height of the tower and the distance between tower and the building.Angle of Elevation Problems
- 32A man on a cliff observes a boat at an angle of depression of which is approaching the shore to the point immediately beneath the observer with a uniform speed. Six minutes later, the angle of depression of the boat is found to be . Find the time taken by the boat from here to reach the shore.Angle of Depression Problems
- 33From the top of a building 60 m high, the angles of depression of the top and bottom of the vertical lamp post are observed to be and respectively. (i) Find the horizontal distance between the building and the lamp post. (ii) Find the distance between the tops of the building and the lamp post.Angle of Depression Problems
- 33From a point on a bridge across the river, the angles of depressions of the banks on opposite sides of the river are and respectively. If the bridge is at a height of 4 m from the banks, find the width of the river.Angle of Depression Problems
- 34From the top of a 45 m high light house, the angles of depression of two ships, on the opposite side of it, are observed to be and . If the line joining the ships passes through the foot of the light house, find the distance between the ships. (Use )Angle of Depression Problems
- 34From a window 15 metres high above the ground in a street, the angles of elevation and depression of the top and the foot of another house on the opposite side of the street are and respectively. Find the height of the opposite house. (Use )Angle of Elevation Problems
- 35The angles of depression of the top and the bottom of a 50 m high building from the top of a tower are and , respectively. Find the height of the tower. (Use )Angle of Depression Problems
- 35The angle of elevation of a jet plane from a point A on the ground is . After a flight of 30 seconds, the angle of elevation changes to . If the jet plane is flying at a constant height of m, find the speed of the jet plane.Angle of Elevation Problems
- 35The angles of depression of the top and the bottom of a 8 m tall building from the top of a multi-storeyed building are and respectively. Find the height of the multi-storeyed building and the distance between the two buildings.Angle of Depression Problems
- 35A pole 6m high is fixed on the top of a tower. The angle of elevation of the top of the pole observed from a point P on the ground is and the angle of depression of the point P from the top of the tower is . Find the height of the tower and the distance of point P from the foot of the tower. (Use )Angle of Elevation Problems
2023
21 q
- 9If a pole 6 m high casts a shadow m long on the ground, then sun's elevation is :
Tap an option to check your answer.
Angle of Elevation Problems - 23Find the length of the shadow on the ground of a pole of height 18 m when angle of elevation of the sun is such that .Angle of Elevation Problems
- 24 (a)The length of the shadow of a tower on the plane ground is times the height of the tower. Find the angle of elevation of the sun.Angle of Elevation Problems
- 24 (b)The angle of elevation of the top of a tower from a point on the ground which is 30 m away from the foot of the tower, is . Find the height of the tower.Angle of Elevation Problems
- 32One observer estimates the angle of elevation to the basket of a hot air balloon to be , while another observer 100 m away estimates the angle of elevation to be . Find : (a) The height of the basket from the ground. (b) The distance of the basket from the first observer's eye. (c) The horizontal distance of the second observer from the basket.Angle of Elevation Problems
- 32A ladder set against a wall at an angle to the ground. If the foot of the ladder is pulled away from the wall through a distance of 4 m, its top slides a distance of 3 m down the wall making an angle with the ground. Find the final height of the top of the ladder from the ground and length of the ladder.Angle of Elevation Problems
- 32 (A)A straight highway leads to the foot of a tower. A man standing on the top of the 75 m high tower observes two cars at angles of depression of and , which are approaching the foot of the tower. If one car is exactly behind the other on the same side of the tower, find the distance between the two cars. (use )Angle of Depression Problems
- 32 (B)From the top of a 7 m high building, the angle of elevation of the top of a cable tower is and the angle of depression of its foot is . Determine the height of the tower.Angle of Elevation Problems
- 33 (a)As observed from the top of a 75 m high lighthouse from the sea-level, the angles of depression of two ships are and . If one ship is exactly behind the other on the same side of the lighthouse, find the distance between the two ships. (Use )Angle of Depression Problems
- 33 (a)The angle of elevation of the top of a tower 24 m high from the foot of another tower in the same plane is . The angle of elevation of the top of second tower from the foot of the first tower is . Find the distance between two towers and the height of the other tower. Also, find the length of the wire attached to the tops of both the towers.Angle of Elevation Problems
- 33 (b)From a point on the ground, the angle of elevation of the bottom and top of a transmission tower fixed at the top of 30 m high building are and , respectively. Find the height of the transmission tower. (Use )Angle of Elevation Problems
- 33 (b)A spherical balloon of radius r subtends an angle of at the eye of an observer. If the angle of elevation of its centre is from the same point, then prove that height of the centre of the balloon is times its radius.Angle of Elevation Problems
- 34The angle of elevation of the top of a vertical tower from a point P on the ground is . From another point Q, 10 m vertically above the first point P, its angle of elevation is . Find : (a) The height of the tower. (b) The distance of the point P from the foot of the tower. (c) The distance of the point P from the top of the tower.Angle of Elevation Problems
- 35 (a)The angle of elevation of the top of a tower 30 m high from the foot of another tower in the same plane is and the angle of elevation of the top of the second tower from the foot of the first tower is . Find the distance between the two towers and also the height of the other tower.Angle of Elevation Problems
- 35An aeroplane when flying at a height of 3000 m from the ground passes vertically above another aeroplane at an instant when the angles of elevation of the two planes from the same point on the ground are and respectively. Find the vertical distance between the aeroplanes at that instant. Also, find the distance of first plane from the point of observation. (Take )Angle of Elevation Problems
- 35Two pillars are standing on either side of a 80 m wide road. Height of one pillar is 20 m more than the height of the other pillar. From a point on the road between the pillars, the angle of elevation of the higher pillar is , whereas that of the other pillar is . Find the position of the point between the pillars and the height of each pillar. (Use )Angle of Elevation Problems
- 35 (b)From the top of a tower 100 m high, a man observes two cars on the opposite sides of the tower with angles of depression and respectively. Find the distance between the two cars. (Use )Angle of Depression Problems
- Radio towers are used for transmitting a range of communication services including radio and television. The tower will either act as an antenna itself or support one or more antennas on its structure. On a similar concept, a radio station tower was built in two Sections A and B. Tower is supported by wires from a point O. Distance between the base of the tower and point O is 36 cm. From point O, the angle of elevation of the top of the Section B is and the angle of elevation of the top of Section A is . Based on the above information, answer the following questions :37 (i)Find the length of the wire from the point O to the top of Section B.Angle of Elevation Problems
- Radio towers are used for transmitting a range of communication services including radio and television. The tower will either act as an antenna itself or support one or more antennas on its structure. On a similar concept, a radio station tower was built in two Sections A and B. Tower is supported by wires from a point O. Distance between the base of the tower and point O is 36 cm. From point O, the angle of elevation of the top of the Section B is and the angle of elevation of the top of Section A is . Based on the above information, answer the following questions :37 (ii) (a)Find the distance AB.Angle of Elevation Problems
- Radio towers are used for transmitting a range of communication services including radio and television. The tower will either act as an antenna itself or support one or more antennas on its structure. On a similar concept, a radio station tower was built in two Sections A and B. Tower is supported by wires from a point O. Distance between the base of the tower and point O is 36 cm. From point O, the angle of elevation of the top of the Section B is and the angle of elevation of the top of Section A is . Based on the above information, answer the following questions :37 (ii) (b)Find the area of .Angle of Elevation Problems
- Radio towers are used for transmitting a range of communication services including radio and television. The tower will either act as an antenna itself or support one or more antennas on its structure. On a similar concept, a radio station tower was built in two Sections A and B. Tower is supported by wires from a point O. Distance between the base of the tower and point O is 36 cm. From point O, the angle of elevation of the top of the Section B is and the angle of elevation of the top of Section A is . Based on the above information, answer the following questions :37 (iii)Find the height of the Section A from the base of the tower.Angle of Elevation Problems
2022
11 q
- 8In Fig. 3, AB is tower of height 50 m. A man standing on its top, observes two cars on the opposite sides of the tower with angles of depression and respectively. Find the distance between the two cars.Angle of Depression Problems
- 9 (a)The angle of elevation of the top of a building from the foot of the tower is and the angle of elevation of the top of the tower from the foot of the building is . If the tower is 50 m high, then find the height of the building.Angle of Elevation Problems
- 8The tops of two poles of heights 20 m and 28 m are connected with a wire. The wire is inclined to the horizontal at an angle of . Find the length of the wire and the distance between the two poles.Angle of Elevation Problems
- 9An aeroplane when flying at a height of 3125 m from the ground passes vertically below another plane at an instant when the angles of elevation of the two planes from the same point on the ground are and respectively. Find the distance between the two planes at that instant.Angle of Elevation Problems
- 9 (b)From a point on a bridge across a river, the angles of depression of the banks on opposite sides of the river are and respectively. If the bridge is at a height of 3 m from the banks, then find the width of the river.Angle of Depression Problems
- 12A straight highway leads to the foot of a tower. A man standing at the top of the tower observes a car at an angle of depression of , which is approaching the foot of the tower with a uniform speed. Ten seconds later, the angle of depression of the car is found to be . Find the time taken by the car to reach the foot of the tower from this point.Angle of Depression Problems
- 12From the top of an 8 m high building, the angle of elevation of the top of a cable tower is and the angle of depression of its foot is . Determine the height of the tower. (Take ).Angle of Elevation Problems
- Kite Festival Kite festival is celebrated in many countries at different times of the year. In India, every year January is celebrated as International Kite Day. On this day many people visit India and participate in the festival by flying various kinds of kites. The picture given below, shows three kites flying together. In Fig. 5, the angles of elevation of two kites (Points A and B) from the hands of a man (Point C) are found to be and respectively. Taking AD = 50 m and BE = 60 m, find13 (1)the lengths of strings used (take them straight) for kites A and B as shown in the figure.Angle of Elevation Problems
- Kite Festival Kite festival is celebrated in many countries at different times of the year. In India, every year January is celebrated as International Kite Day. On this day many people visit India and participate in the festival by flying various kinds of kites. The picture given below, shows three kites flying together. In Fig. 5, the angles of elevation of two kites (Points A and B) from the hands of a man (Point C) are found to be and respectively. Taking AD = 50 m and BE = 60 m, find13 (2)the distance ‘d’ between these two kitesAngle of Elevation Problems
- Gadisar Lake is located in the Jaisalmer district of Rajasthan. It was built by the King of Jaisalmer and rebuilt by Gadsi Singh in century. The lake has many Chhatris. One of them is shown below : Observe the picture. From a point A m above from water level, the angle of elevation of top of Chhatri (point B) is and angle of depression of its reflection in water (point C) is . If the height of Chhatri above water level is (approximately) 10 m, then14 (a)draw a well-labelled figure based on the above information;Angle of Elevation Problems
- Gadisar Lake is located in the Jaisalmer district of Rajasthan. It was built by the King of Jaisalmer and rebuilt by Gadsi Singh in century. The lake has many Chhatris. One of them is shown below : Observe the picture. From a point A m above from water level, the angle of elevation of top of Chhatri (point B) is and angle of depression of its reflection in water (point C) is . If the height of Chhatri above water level is (approximately) 10 m, then14 (b)find the height of the point A above water level. (Use )Angle of Elevation Problems
The 10 board questions to practise first
The questions the board asked again come first, most asked first. Each one says how often and when.
Question 1
Asked 3 times: 2023, 2024, 2026
9If the length of the shadow of a tower is times that of its height, then altitude of the Sun is :Tap an option to check your answer.
Question 2
Asked 3 times: 2022*, 2024*, 2026 (* = numbers or wording changed that year)
34 (b)A tower stands vertically on the ground. A man standing at the top of the tower observes his friend at an angle of depression of , who is approaching the foot of the tower with a uniform speed. 30 seconds later, the angle of depression changes to . Find the time taken by his friend to reach the foot of the tower from this point.Question 3
Asked 3 times: 2023*, 2024*, 2026 (* = numbers or wording changed that year)
12From 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 . The height (in metres) of the tower is :Tap an option to check your answer.
Question 4
Asked 3 times: 2024*, 2025*, 2026 (* = numbers or wording changed that year)
34 (a)The angle of elevation of the top of a building from a point A, on the ground, is . On moving a distance of 24 m towards its base to the point B, the angle of elevation changes to . Find the height of the building and distance of point A from the base of the building. (Take )Question 5
Asked 3 times: 2022*, 2023*, 2024 (* = numbers or wording changed that year)
34From a window 15 metres high above the ground in a street, the angles of elevation and depression of the top and the foot of another house on the opposite side of the street are and respectively. Find the height of the opposite house. (Use )Question 6
Asked 3 times: 2022*, 2023*, 2024 (* = numbers or wording changed that year)
34From the top of a 45 m high light house, the angles of depression of two ships, on the opposite side of it, are observed to be and . If the line joining the ships passes through the foot of the light house, find the distance between the ships. (Use )Question 7
Asked 2 times: 2023*, 2026 (* = numbers or wording changed that year)
32A 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 and respectively. Find the height of the tower and lengths of the wires attached. (Take )Question 8 (case study, 4 parts)
Asked 2 times: 2023*, 2026 (* = numbers or wording changed that year)
Radio towers are used for transmitting a range of communication services including radio and television. The tower will either act as an antenna itself or support one or more antennas on its structure. On a similar concept, a radio station tower was built in two sections ‘A’ and ‘B’. Tower is supported by wires from a point ‘O’ (as shown in figure). Distance between the base of the tower and point ‘O’ is 6 m. From point ‘O’, the angle of elevation of the top of the section ‘B’ is and the angle of elevation of the top of section ‘A’ is . Based on the above information, answer the following questions :37 (i)Find the length of the wire from the point ‘O’ to the top of section ‘B’.37 (ii)Find the length of the wire from the point ‘O’ to the top of section ‘A’.37 (iii) (a)Find the distance AB.37 (iii) (b)Find the area of .Question 9
Asked 2 times: 2025*, 2026 (* = numbers or wording changed that year)
9The string of a flying kite is tied to a point on the ground. The length of the string between the kite and the point on the ground is 80 m. The string makes an angle of with the ground. The height of the kite above the ground is :Tap an option to check your answer.
Question 10
Asked 2 times: 2024*, 2025 (* = numbers or wording changed that year)
35 (a)The angle of elevation of an airborne helicopter from a point A on the ground is . After a flight of 15 seconds, the angle of elevation of the helicopter changes to . If the helicopter is flying at a constant height of 2000 m, find the speed of the helicopter. (Take )