Mathematics ECAT Pre Engineering Chapter 14 Application of Trigonometry Online Test

The quadratic equation 8 sec2θ - 6 secθ +1 =0 has

• Infinitely many roots A
• Exactly two roots B
• Exactly four roots C
• No roots D

The upper 3/4 the portion of a vertical pole subtends an angle tan^-13/5 at a point in the horizontal plane through its foot and at a distance 40 m from the foot. A possible height of the vertical pole is

• 20 m A
• 40 m B
• 60 m C
• 80 m D

E-radius corresponding to < A is

• 
  A
• 
  B
• 
  C
• 
  D

A circle which touches one side of a triangle extermally and the other two sides produced is called

• In-circle A
• Circumcircle B
• e-circle C
• Point circle D

The law of sines can be used to solve

• Right angle triangle A
• Isosceles triangle B
• oblique triangle C
• haxagon D

A chimney is such that on walking towards it 50 m in a horizontal line through its base the angular elevation of its top changes from 30° to 45°. The height of the chimney is

• 
  A
• 
  B
• 
  C
• 
  D

A tower subtends an angleαat a point on the same level as the root of the tower and at a second point, b meters above the first, the angle of depression of the foot of the tower isβ. The height of the tower is

• b cotαtanβ A
• b tanαtanβ B
• b tanαcotβ C
• None of these D

• 
  A
• 
  B
• 
  C
• 
  D

A kite flying at a height of 67.2 m is attached to a fully stretched string inclined at an angle of 53 to the horizontal, the length of the string

• 62m A
• 82m B
• 73m C
• 57m D

For any equilateral r :R :η :r1 :r2 :r3 =

• 1:2:3:4:5 A
• 1:2:3:3:3 B
• 1:2:4:4:4 C
• 2:1 :2 :2 :2 D

e-radii are denoted by

• η A
• r2 B
• r3 C
• All of these D

• 
  A
• 
  B
• 
  C
• 
  D

An airplane flying at height of 300 meters above the ground passes vertically above another plane at an instant when the angle of elevation of the two planes from the same point on the ground are 60° and 45° respectively. Then the height of the lower plane from the ground is (in meters).

• 
  A
• 
  B
• 
  C
• 
  D

IfΔABC is right, law of cosine reduce to

• Law of sine A
• Law of tangent B
• Phthogorous theorem C
• Hero's formula D

The towers each 120 meters high are 800 meters apart. The measure of the angle of elevation from the base of one tower to the top of the other is

• 12^𝜊 A
• 9^𝜊 B
• 7^𝜊 C
• -120^𝜊 D

• The law of sines A
• The law of tangents B
• The pythagorus theorem C
• None of these D

If sided of𝜟ABC are 16,20,and 33, then the value of the greatests angle to

• 150𝜊 20' A
• 132𝜊 35' B
• 101𝜊 25' C
• 160𝜊 50' D

The angle of elevation of the tops of two towers at the middle point of the line joining the foots of the tower are 60^οand 30^οrespectively. The the ratio of the heghts of the tower is

• 2 : 1 A
• 3 : 1 B
• 1 : 2 C
• 1 : 3 D

• 
  A
• 
  B
• 
  C
• 
  D

The angle of elevation of the top of a tree from a point 17 meters from is foot is 42^𝜊The height of the tree is

• 12m A
• 21m B
• 17m C
• 15m D

• 
  A
• 
  B
• 
  C
• 
  D

E-radius corresponding to < C is

• 
  A
• 
  B
• 
  C
• 
  D

• 
  A
• 
  B
• 
  C
• 
  D

A person standing on the bank of a river finds that the angle of elevation of the top of a tower on the opposite bank is 45°. then which of the following statements is correct?

• Breadth of the river is twice the height of the tower A
• Breadth of the river an the height of the tower are the same B
• Breadth of the river is half of the height of the tower C
• None of these D

If a, b, c are the measures of the sides of a triangle then

• 
  A
• 
  B
• 
  C
• 
  D

• 
  A
• 
  B
• 
  C
• 
  D

PQ is a post of given height a, and AB is a tower at some distance;αandβare the angles of elevation of B, the top of the tower, at P and Q respectively. The height of the tower and its distance from the post are

• 
  A
• 
  B
• 
  C
• 
  D

• The law of of sines A
• The law of tangents B
• The law of consines C
• None of these D

• R A
• 2R B
• r C
• 2r D

A man of height 6 ft observes the top of a tower and the foot of the tower at angles of 45° and 30° of elevation and depression respectively. The height of the tower is

• 
  A
• 
  B
• 
  C
• 
  D