Question

1. The temperature indicating instrument in vehicles indicates the temperature of

(A) Engine piston

(B) Engine cylinder

(C) Lubricating oil

(D) Jacket cooling water

2. The motion of the cam is transferred to the valves through



Piston

Rocker arms

Camshaft pulley

Valve stems

3. The power actually developed inside the engine cylinder is called as



(A) Indicated power

(B) Brake power

(C) Frictional power

(D) None of these

4. If the air-fuel mixture in a spark ignition engine is too rich, then air-fuel ratio is about



17:1

15:1

13:1

10:1

5. Petrol that detonates easily is called



High octane petrol

Low octane petrol

Unleaded petrol

Blended fuel



6. The calorific value of Diesel is about



36.5 MJ/kg

38.5 MJ/kg

42.5 MJ/kg

45.5 MJ/kg



7. The function of oil control rings is that it



(A) Lubricates the cylinder wall by releasing oil from its hole

(B) Keeps the cylinder wall lubricated by holding oil in its channel

(C) Prevents engine oil from going into the combustion chamber and returns excess lubricating oil off the cylinder wall through the return holes in the piston to the oil pan

(D) Maintains a seal and prevents escape of burned gases and oil leakage

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Answer 1

Answer:

1.The temperature indicating instrument in vehicles indicates the temperature of (D) Jacket cooling water.

2. The motion of the cam is transferred to the valves through (B) Rocker arms.

3. The power actually developed inside the engine cylinder is called as (A) Indicated power

4. If the air-fuel mixture in a spark ignition engine is too rich, then air-fuel ratio is about (D) 10:1

5. Petrol that detonates easily is called (B) Low octane petrol

6.The calorific value of Diesel is about (D) 45.5 MJ/kg

7. The function of oil control rings is that it (C) Prevents engine oil from going into the combustion chamber and returns excess lubricating oil off the cylinder wall through the return holes in the piston to the oil pan

Explanation:

• Jacket cooling water: Fresh water is used as a cooling substance inside an engine, which can circulate inside the passage of engine.
• Rocker Arms: This is a part of any automobile. Basically its function is to pass the motion to the valve.
• Indicated power: The total power inside the engine cylinder. Indicated power = Brake power + Frictional power
• Air-fuel ratio: The mass ratio of air to the fuel which is used in combustion purpose.
• Low octane petrol: In this case petrol has lower compression rate and detonates easily.
• Calorific value of Diesel: By burning diesel of mass 1 unit, the heat produced is called calorific value of diesel.