83. Which of the following chemicals are the ingredients of the mixture used for comparing the
ignition quality (knocking tendency) of S.I Engines fuels?

൫ Iso-Octane.

@) @-methyl naphthalene.

(17) n-heptane.

(iv) hepta-methyl nonane.
(A) @ and (iv) (B) (ii) and (iii)
(C) 61) ೩೫4 69 ൯൬) (0 ೩೧6 (10)

84. What is the effect of short ignition delay, in knocking tendency of 4 stroke I.C. Engines?
(A) Reduces the knocking tendency in both petrol and diesel engines

(B) Increases the knocking tendency in diesel engines and reduces the knocking
tendency in petrol engines

(C) Reduces the knocking tendency in diesel engines and increases the knocking
tendency in petrol engines

(D) Increases the knocking tendency in both the petrol engines and diesel engines

85. Which of the following statements is correct regarding G.D.I. electronic fuel Injection system?
(^) The fuel is directly injected into the venturi
(B)_ The fuel is directly injected into the throttle body
(C) The fuel is directly injected into the intake port

(0) The fuel is directly injected into the engine cylinder or combustion chamber

86. Which of the following statements are correct regarding Cohran Boilers?
0) 16 15 8 water tube boiler.
Gi) It isa horizontal boiler.
(17) It is a fire tube boiler.
(0५) It is a vertical boiler.
(^) i) and (iii) are correct (8). (0) and (ii) are correct

(C) ii) and (iv) are correct (7) @ and (iv) are correct

87. The compression ratio of a square engine having a cylinder bore of 8 cm and clearance
volume of 167 cm? :

(A) 9:1 (B) 10:1
(0 8:1 ൩൬ 11:1
227/2028 16 A