CBSE Board Practice

CBSE Grade X - Some Applications of Trigonometry
Question 1
1.
The angles of depression of two boats from the top of a cliff 150 m high are 45° and 30° respectively. Find the distance between the boats, if the boats are on the opposite sides of the cliff .
  • 422.82 m
  • 407.82 m
  • 416.82 m
  • 394.82 m
  • 409.82 m
Question 2
2.
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 45° and the angle of elevation of the top of the building is 30°. If the height of the building is 15 m, find the height of the flag staff .
  • 10.98 m
  • 15.98 m
  • 5.98 m
  • 13.98 m
  • 7.98 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
    • sin
      (-1)
       
      (
      3

      4
      )
    • .
    • If the distance between the point and the top of the
    • tower
    • is
    • 60 m
    • ,
    • find the height of the
    • tower
    • .
  • 48.00 m
  • 40.00 m
  • 50.00 m
  • 45.00 m
  • 42.00 m
Question 4
4.
The angles of depression of two boats from the top of a cliff 110 m high are 45° and 30° respectively. Find the distance between the boats, if the boats are on the same side of the cliff .
  • 80.53 m
  • 83.53 m
  • 85.53 m
  • 75.53 m
  • 77.53 m
Question 5
5.
Two vertical poles are on either side of a road. A 29 m long ladder is placed between the two poles. When the ladder rests against one pole, it makes an angle of 45° with the pole and when it is turned to rest against another pole, it makes an angle of 30° with the road. Find the width of the road.
  • 45.62 m
  • 42.62 m
  • 40.62 m
  • 48.62 m
  • 50.62 m
Question 6
6.
    • The upper part of a tree is broken into two parts without being detatched. It makes an angle of 47°5' with the ground. The top of the tree touches the ground at a distance of 140 m from the foot of the tree . Find the height of the tree before it was broken.
    • From Table of Natural Tangents
      0'
      6'
      12'
      18'
      24'
      30'
      36'
      42'
      48'
      54'
      1'
      2'
      3'
      4'
      5'
      47
      1.0724
      1.0761
      1.0799
      1.0837
      1.0875
      1.0913
      1.0951
      1.0990
      1.1028
      1.1067
      6
      13
      19
      25
      32
    • From Table of Natural Cosines
      0'
      6'
      12'
      18'
      24'
      30'
      36'
      42'
      48'
      54'
      1'
      2'
      3'
      4'
      5'
      47
      0.6820
      0.6807
      0.6794
      0.6784
      0.6769
      0.6756
      0.6743
      0.6730
      0.6717
      0.6704
      2
      4
      6
      9
      11
  • 343.19 m
  • 356.19 m
  • 360.19 m
  • 350.19 m
  • 373.19 m
Question 7
7.
    • An observer 1.4 m tall, is 70 m away from a tower . The angle of elevation of the top of the tower from her eyes is 57°11'. Find the height of the tower .
    • From Table of Natural Tangents
      0'
      6'
      12'
      18'
      24'
      30'
      36'
      42'
      48'
      54'
      1'
      2'
      3'
      4'
      5'
      57
      1.5399
      1.5458
      1.5517
      1.5577
      1.5637
      1.5697
      1.5757
      1.5818
      1.5880
      1.5941
      10
      20
      30
      40
      50
  • 109.96 m
  • 82.96 m
  • 97.96 m
  • 124.96 m
  • 113.96 m
Question 8
8.
A man on the top of a vertical observation tower observes a car moving at a uniform speed coming directly towards him. If it takes 6 min for the angle of depression to change from 30° to 60°, how soon after this, will the car reach the observation tower?
  • 2 min 4 sec
  • 6 min 7 sec
  • 3 min 0 sec
  • 0 min 3 sec
  • 4 min 6 sec
Question 9
9.
    • 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 58°49'. If the height of the radio tower is 4 m, find the distance between the observation point and the top of the radio tower.
    • From Table of Natural Tangents
      0'
      6'
      12'
      18'
      24'
      30'
      36'
      42'
      48'
      54'
      1'
      2'
      3'
      4'
      5'
      58
      1.6003
      1.6066
      1.6128
      1.6191
      1.6255
      1.6319
      1.6383
      1.6447
      1.6512
      1.6577
      11
      21
      32
      43
      53
    • From Table of Natural Sines
      0'
      6'
      12'
      18'
      24'
      30'
      36'
      42'
      48'
      54'
      1'
      2'
      3'
      4'
      5'
      58
      0.8450
      0.8490
      0.8499
      0.8508
      0.8517
      0.8526
      0.8536
      0.8545
      0.8554
      0.8563
      2
      3
      5
      6
      8
  • 4.68 m
  • 5.68 m
  • 3.68 m
  • 6.68 m
  • 2.68 m
Question 10
10.
Two poles of equal height are standing opposite to each other on either side of a road which is 20 m wide. From a point between them on the road, the angles of elevation of the top of the poles are 45° and 60° respectively. Find the height of each pole and the distances of the point from the two poles .
      • height =
      • 13.68 m
      • , distances away =
      • 8.32 m
      • ,
      • 13.68 m
      • height =
      • 14.68 m
      • , distances away =
      • 9.32 m
      • ,
      • 14.68 m
      • height =
      • 11.68 m
      • , distances away =
      • 6.32 m
      • ,
      • 11.68 m
      • height =
      • 12.68 m
      • , distances away =
      • 7.32 m
      • ,
      • 12.68 m
      • height =
      • 10.68 m
      • , distances away =
      • 5.32 m
      • ,
      • 10.68 m