ECAT Pre Engineering MCQ Test With Answer for Chapter 14 Mathematics

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

• 
  A
• 
  B
• 
  C
• 
  D

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

• 
  A
• 
  B
• 
  C
• 
  D

Area ofΔABC=

• ab sinα A
• 1/2 ab sinα B
• 1/2 ac sinγ C
• 1/2 ac sinβ D

A circle drawn inside a triangle and touching its sides is called

• In-circle A
• Circum circle B
• Escribed circle C
• None of these D

If five triangles are constructed having sides of the lengths indicated below, the triangle that will NOT be a right triangle is

• 8, 15, 17 A
• 3, 4, 5 B
• 12, 15, 18 C
• 5, 12, 13 D

• 
  A
• 
  B
• 
  C
• 
  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-radii are denoted by

• η A
• r2 B
• r3 C
• All of these D

• 
  A
• 
  B
• 
  C
• 
  D

If Cosθ=0, thenθ= ______

• nπ/2 A
• (2n + 1)π/2 B
• (2n - 1)π/2 C
• (4n + 1)π/2 D

In-radius is denoted by

• r A
• η B
• r2 C
• R D

The process of finding the unknown elements in triangle is called the

• solution of the triangle A
• Mean differnece B
• Engineering distance C
• angle of depressin D

E-radius corresponding to < B is

• 
  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

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

• R A
• 2R B
• r C
• 2r D

The longer side of a parallelogram is 10 cm and the shorter is 6 cm. If the longer diagonal makes an angles 30° with the longer side, the length of the longer diagonal is

• 
  A
• 
  B
• 
  C
• 
  D

If the flag-staff 6 meters high placed on the top of a tower. Makes the shadow 2√3 m on the ground, then the angle of elevation of the sun is

• 30^ο A
• 35^ο B
• 45^ο C
• 60^ο 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 observes that the angle subtended by a tree of the opposite bank is 60°, when he retreats 40 m from the bank, he finds the angle to be 30°. The height of the tree and the breadth of the river are

• 
  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

In triangle ABC, in which b=95, c=34, a =52^𝜊then the value of a=

• 18 cm A
• 18.027 cm B
• 20.7 cm C
• 19 cm 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

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

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

E-radius corresponding to < A is

• 
  A
• 
  B
• 
  C
• 
  D