EduSahara™ Assignment
Name : Heights and Distances
Chapter : Some Applications of Trigonometry
Grade : CBSE Grade X
License : Non Commercial Use
Question 1
1.
    • A
    • building
    • stands vertically on the ground.
    • From a point on the ground,
    • the angle of elevation
    • of the top of the
    • building
    • is found to be
    • 60°
    • .
    • If the height of the
    • building
    • is
    • 180 m
    • ,
    • find the distance between
    • the observation point and the top of the
    • building
    • .
  • (i)
    120



    3
    m
  • (ii)
    180



    2
    m
  • (iii)
    360
    m
  • (iv)
    120
    m
  • (v)
    120



    18
    m
Question 2
2.
    • A
    • radio tower
    • stands vertically on the ground.
    • From a point on the ground,
    • the angle of elevation
    • of the top of the
    • radio tower
    • is found to be
    • 45°
    • .
    • If the height of the
    • radio tower
    • is
    • 190 m
    • ,
    • find the distance between
    • the observation point and the foot of the
    • radio tower
    • .
  • (i)
    188
    m
  • (ii)
    192
    m
  • (iii)
    190
    m
  • (iv)
    189
    m
  • (v)
    191
    m
Question 3
3.
    • A
    • tower
    • stands vertically on the ground.
    • From a point on the ground,
    • the angle of elevation
    • of the top of the
    • tower
    • is found to be
    • 60°
    • .
    • If the distance between the point and the foot of the
    • tower
    • is
    • 140 m
    • ,
    • find the distance between
    • the observation point and the top of the
    • tower
    • .
  • (i)
    283
    m
  • (ii)
    279
    m
  • (iii)
    281
    m
  • (iv)
    278
    m
  • (v)
    280
    m
Question 4
4.
    • A
    • radio tower
    • stands vertically on the ground.
    • From a point on the ground,
    • the angle of elevation
    • of the top of the
    • radio tower
    • is found to be
    • 60°
    • .
    • If the distance between the point and the foot of the
    • radio tower
    • is
    • 60 m
    • ,
    • find the height of the
    • radio tower
    • .
  • (i)
    60



    18
    m
  • (ii)
    60



    3
    m
  • (iii)
    90



    2
    m
  • (iv)
    180
    m
  • (v)
    60
    m
Question 5
5.
    • A
    • chimney
    • stands vertically on the ground.
    • From a point on the ground,
    • the angle of elevation
    • of the top of the
    • chimney
    • is found to be
    • 60°
    • .
    • If the distance between the point and the top of the
    • chimney
    • is
    • 40 m
    • ,
    • find the height of the
    • chimney
    • .
  • (i)
    20



    18
    m
  • (ii)
    20
    m
  • (iii)
    30



    2
    m
  • (iv)
    20



    3
    m
  • (v)
    60
    m
Question 6
6.
    • A
    • radio tower
    • stands vertically on the ground.
    • From a point on the ground,
    • the angle of elevation
    • of the top of the
    • radio tower
    • is found to be
    • 45°
    • .
    • If the distance between the point and the top of the
    • radio tower
    • is
    • 10 m
    • ,
    • find the distance between
    • the observation point and the foot of the
    • radio tower
    • .
  • (i)
    5



    2
    m
  • (ii)
    5

    2



    12
    m
  • (iii)
    10



    3
    m
  • (iv)
    5
    m
  • (v)
    10
    m
Question 7
7.
Two boys are on opposite sides of a tower of 190 m height. They measure the angle of elevation of the top of the tower as 30° and 45° respectively. Find the distance between the two boys.
  • (i)
    (
    190



    3
    +
    190
    )
    m
  • (ii)
    (
    2
    +



    3
    )
    m
  • (iii)
    72200
    m
  • (iv)
    (
    190



    18
    +
    190



    6
    )
    m
  • (v)
    (
    285



    2
    +
    95



    6
    )
    m
Question 8
8.
A person, walking 30 m from a point toward a flagpost , observes that its angle of elevation changes from 45° to 60°. Find the height of the flagpost .
  • (i)
    (
    45
    +
    15



    3
    )
    m
  • (ii)
    (
    45

    2



    6
    +
    45

    2



    2
    )
    m
  • (iii)
    (
    2
    +



    3
    )
    m
  • (iv)
    1350
    m
  • (v)
    (
    45



    6
    +
    15



    18
    )
    m
Question 9
9.
A flagstaff stands on the top of a building at a distance of 30 m away from the foot of building . The angle of elevation of the top of the flagstaff is 60° and the angle of elevation of the top of the building is 45°. Find the height of the flagstaff .
  • (i)
    (
    30



    18
    30



    6
    )
    m
  • (ii)
    1800
    m
  • (iii)
    (
    2



    3
    )
    m
  • (iv)
    (
    30



    3
    30
    )
    m
  • (v)
    (
    45



    2
    15



    6
    )
    m
Question 10
10.
    • A
    • tower
    • stands vertically on the ground.
    • From a point on the ground,
    • the angle of elevation
    • of the top of the
    • tower
    • is found to be
    • sin
      (-1)
       
      (
      1

      3
      )
    • .
    • If the distance between the point and the top of the
    • tower
    • is
    • 20 m
    • ,
    • find the height of the
    • tower
    • .
  • (i)
    8.67 m
  • (ii)
    4.67 m
  • (iii)
    6.67 m
  • (iv)
    7.67 m
  • (v)
    5.67 m
Question 11
11.
    • A
    • tower
    • stands vertically on the ground.
    • From a point on the ground,
    • the angle of elevation
    • of the top of the
    • tower
    • is found to be
    • cos
      (-1)
       
      (
      6

      7
      )
    • .
    • If the distance between the point and the top of the
    • tower
    • is
    • 10 m
    • ,
    • find the distance between
    • the observation point and the foot of the
    • tower
    • .
  • (i)
    8.57 m
  • (ii)
    9.57 m
  • (iii)
    10.57 m
  • (iv)
    7.57 m
  • (v)
    6.57 m
Question 12
12.
    • A
    • tower
    • stands vertically on the ground.
    • From a point on the ground,
    • the angle of elevation
    • of the top of the
    • tower
    • is found to be
    • tan
      (-1)
       
      (
      1

      2
      )
    • .
    • If the distance between the point and the foot of the
    • tower
    • is
    • 30 m
    • ,
    • find the height of the
    • tower
    • .
  • (i)
    12.00 m
  • (ii)
    15.00 m
  • (iii)
    10.00 m
  • (iv)
    18.00 m
  • (v)
    20.00 m
Question 13
13.
    • A
    • tower
    • stands vertically on the ground.
    • From a point on the ground,
    • the angle of elevation
    • of the top of the
    • tower
    • is found to be
    • cosec
      (-1)
       
      (
      16

      9
      )
    • .
    • If the distance between the point and the top of the
    • tower
    • is
    • 50 m
    • ,
    • find the height of the
    • tower
    • .
  • (i)
    23.12 m
  • (ii)
    25.12 m
  • (iii)
    33.12 m
  • (iv)
    31.12 m
  • (v)
    28.12 m
Question 14
14.
    • A
    • tower
    • stands vertically on the ground.
    • From a point on the ground,
    • the angle of elevation
    • of the top of the
    • tower
    • is found to be
    • sec
      (-1)
       
      (
      7

      4
      )
    • .
    • If the distance between the point and the top of the
    • tower
    • is
    • 60 m
    • ,
    • find the distance between
    • the observation point and the foot of the
    • tower
    • .
  • (i)
    31.29 m
  • (ii)
    29.29 m
  • (iii)
    37.29 m
  • (iv)
    34.29 m
  • (v)
    39.29 m
Question 15
15.
    • A
    • tower
    • stands vertically on the ground.
    • From a point on the ground,
    • the angle of elevation
    • of the top of the
    • tower
    • is found to be
    • cot
      (-1)
       
      (
      2

      3
      )
    • .
    • If the height of the
    • tower
    • is
    • 100 m
    • ,
    • find the distance between
    • the observation point and the foot of the
    • tower
    • .
  • (i)
    63.67 m
  • (ii)
    69.67 m
  • (iii)
    61.67 m
  • (iv)
    71.67 m
  • (v)
    66.67 m
Question 16
16.
    • A
    • tower
    • stands vertically on the ground.
    • The height of the
    • tower
    • is
    • 160
      m
    • .
    • The distance between the observation point and its foot
    • is
    • 160
      m
    • .
    • Find the angle of elevation.
  • (i)
    75°
  • (ii)
    45°
  • (iii)
    30°
  • (iv)
    105°
  • (v)
    60°
Question 17
17.
The upper part of a tree is broken into two parts without being detatched. It makes an angle of 60° with the ground. The top of the tree touches the ground at a distance of 150 m from the foot of the tree . Find the height of the tree before it was broken.
  • (i)
    557.82 m
  • (ii)
    543.82 m
  • (iii)
    567.82 m
  • (iv)
    559.82 m
  • (v)
    585.82 m
Question 18
18.
There are two temples one on each bank of a river, just opposite to each other. One of the temples is 10 m high. As observed from the top of this temple, the angles of depression of the top and foot of the other temple are 30° and 45° respectively. Find the width of the river .
  • (i)
    15.00 m
  • (ii)
    13.00 m
  • (iii)
    7.00 m
  • (iv)
    5.00 m
  • (v)
    10.00 m
Question 19
19.
There are two temples one on each bank of a river, just opposite to each other. One of the temples is 190 m high. As observed from the top of this temple, the angles of depression of the top and foot of the other temple are 30° and 60° respectively. Find the height of the other temple.
  • (i)
    112.66 m
  • (ii)
    134.66 m
  • (iii)
    126.66 m
  • (iv)
    154.66 m
  • (v)
    111.66 m
Question 20
20.
An observer 1.6 m tall, is 150 m away from a tower . The angle of elevation of the top of the tower from her eyes is 30°. Find the height of the tower .
  • (i)
    85.21 m
  • (ii)
    93.21 m
  • (iii)
    91.21 m
  • (iv)
    83.21 m
  • (v)
    88.21 m
Question 21
21.
Two poles of equal height are standing opposite to each other on either side of a road which is 15 m wide. From a point between them on the road, the angles of elevation of the top of the poles are 30° and 45° respectively. Find the height of each pole and the distances of the point from the two poles .
  • (i)
      • height =
      • 5.49 m
      • , distances away =
      • 5.49 m
      • ,
      • 9.51 m
  • (ii)
      • height =
      • 6.49 m
      • , distances away =
      • 6.49 m
      • ,
      • 10.51 m
  • (iii)
      • height =
      • 3.49 m
      • , distances away =
      • 3.49 m
      • ,
      • 7.51 m
  • (iv)
      • height =
      • 4.49 m
      • , distances away =
      • 4.49 m
      • ,
      • 8.51 m
  • (v)
      • height =
      • 7.49 m
      • , distances away =
      • 7.49 m
      • ,
      • 11.51 m
Question 22
22.
From the top of a light house which is 50 m high from the sea level, the angles of depression of two ships are 60° and 45°. If one ship is exactly behind the other on the same side of the light house , find the distance between the two ships.
  • (i)
    26.13 m
  • (ii)
    21.13 m
  • (iii)
    24.13 m
  • (iv)
    18.13 m
  • (v)
    16.13 m
Question 23
23.
From the top of a 13 m high building , the angle of elevation of the top of a cable tower is 45° and the angle of depression of its foot is 30°. Find the height of the cable tower.
  • (i)
    32.51 m
  • (ii)
    35.51 m
  • (iii)
    40.51 m
  • (iv)
    38.51 m
  • (v)
    30.51 m
Question 24
24.
The angle of elevation of the top of a building from the foot of a tower is 30°. The angle of elevation of the top of the tower from the foot of the building is 45°. If the height of the tower is 55 m, find the height of the building .
  • (i)
    36.76 m
  • (ii)
    28.76 m
  • (iii)
    26.76 m
  • (iv)
    31.76 m
  • (v)
    34.76 m
Question 25
25.
A flag is hoisted at the top of a building . From a point on the ground, the angle of elevation of the top of the flag staff is 60° and the angle of elevation of the top of the building is 30°. If the height of the building is 12 m, find the height of the flag staff .
  • (i)
    19.00 m
  • (ii)
    21.00 m
  • (iii)
    24.00 m
  • (iv)
    27.00 m
  • (v)
    29.00 m
Question 26
26.
A flag is hoisted at the top of a building . From a point on the ground, the angle of elevation of the top of the flag staff is 60° and the angle of elevation of the top of the building is 45°. If the height of the flag staff is 11 m, find the height of the building .
  • (i)
    12.03 m
  • (ii)
    10.03 m
  • (iii)
    15.03 m
  • (iv)
    20.03 m
  • (v)
    18.03 m
    Assignment Key

  •  1) (i)
  •  2) (iii)
  •  3) (v)
  •  4) (ii)
  •  5) (iv)
  •  6) (i)
  •  7) (i)
  •  8) (i)
  •  9) (iv)
  •  10) (iii)
  •  11) (i)
  •  12) (ii)
  •  13) (v)
  •  14) (iv)
  •  15) (v)
  •  16) (ii)
  •  17) (iv)
  •  18) (v)
  •  19) (iii)
  •  20) (v)
  •  21) (i)
  •  22) (ii)
  •  23) (ii)
  •  24) (iv)
  •  25) (iii)
  •  26) (iii)