Automobile Engineering Multiple Choice Questions and Answers for Competitive Exams - Automobile Engineering MCQs Set1 - Preparation for GATE Exams

1. In commercial vehicle layouts engine is located forward, rear or under floor mainly to
a. Better utilization of space
b. Increase fuel economy
c. Better weight distribution
d. Reduce the weight of chassis

Ans: c

2. The type of air cycle used in diesel engine is called
a. Otto cycle
b. Carnot cycle
c. Diesel cycle
d. Rankine cycle

Ans: c

3. During suction stroke the pressure inside the cylinder is
a. Equal to atmospheric pressure
b. Above atmospheric pressure
c. Above or below atmospheric pressure
d. Below atmospheric pressure

Ans: d

4. During compression stroke the air is compressed according to
a. Isothermal process
b. Hyperbolic process
c. Adiabatic process
d. Constant pressure process

Ans: c

5. The heat is added in the cycle at
a. Constant pressure
b. Constant volume
c. Approximately constant pressure and constant volume

Ans: c

6. The fuel injected when pressure in the cylinder reaches the point ........... on the curve
a. 1
b. 2
c. 3
d. 4
Ans: c

7. The crankcase scavenging the the crankcase or underside of the piston acts as
a. An air compressor
b. A blower
c. A ventilator
d. A breather
Ans: a

8. The two-stroke engine has valve ports in the
a. Pistons
b. Cylinder walls
c. Piston rings
Ans: b

9. The temperature of the piston will be more at
a. The piston walls
b. The crown of the piston
c. The skirt of the piston
d. The piston pin
Ans: b

10. Connecting rods are generally of the following from
a. Forged round section steel
b. Cast steel triangular section
c. Forged square section steel
d. Forged I section steel
Ans: d

11. For petrol engines the nominal compression ratio will vary between
a. 1 to 2:1
b. 18 to 21:1
c. 1 to 5:1
d. 7.5 to 8.5:1
Ans: d

12. For diesel engines the nominal compression ratio is from
a. 17 to 21:1
b. 7.5 to 8.5:1
c. 30 to 40:1
d. 1 to 5:1
Ans: a

13. One of the major causes of FHP in an engine is
a. High speed
b. High volumetric efficiency
c. Piston-ring friction
Ans: c

14. Engine torque is highest at
a. Low speed
b. Intermediate speed
c. High speed
Ans: b

15. The maximum pressure of air fuel mixture at the end of compression in petrol engines varies from
a. 10-30 Kg/cm2 b. 30-100 Kg/cm2
c. 6-10 Kg/cm2
d. 100-1000 Kg/cm2
Ans: a

16. When we lift a 10 kg weight, 3 metre we would be doing
a. 300 m kg of work
b. 3 m kg of work
c. 30 m kg of work
Ans: c

17. The characteristic of an object which makes it resist any tendency to change its direction of motion is
called
a. Inertia
b. Power
c. Internal energy
Ans: a

18. The maximum pressure of air at the end of compression in diesel engines is about
a. 10 Kg/cm2
b. 100 Kg/cm2
c. 300 Kg/cm2
d. 30 Kg/cm2
Ans: d

19. As the number of cylinders in multi cylinder engines increases the power to weight ratio .........
a. Remains the same
b. Increases
c. Becomes zero
d. Decreases
Ans: b

20. The type of friction generally present in an automotive engine is
a. Viscous friction
b. Greasy friction
c. Dry friction
Ans: a

21. The fit of the piston to the cylinder is measured at the
a. Piston skirt
b. Piston head
c. Point of minimum diameter
Ans: b

22. Vibration damper ..........
a. controls the torsional vibrations
b. drives the pulley
c. dampens the engine speed
d. reduces the speed of the flywheel
Ans: a

23. In a six cylinder engine there is balance of
a. Primary forces only
b. Secondary forces only
c. Both primary and secondary forces
Ans: c

24. If the connecting rod longer, the side thrust of the piston is
a. Increased
b. Constant
c. Decreased
Ans: c

25. In general the design of the current regulator is such that its main actuating winding carries full
a. Generator voltage
b. Generator output
c. Field current
d. Battery voltage
Ans: b

26. Immediately after ignition, combustion chamber temperatures may reach a value of
a. 15000C
b. 55000C
c. 25000C
d. 75000C
Ans: a

27. The compression ratio in a diesel engine is as high as
a. 25:1
b. 20:1
c. 10:1
d. 5:1
Ans: b

28. The temperature of the compressed air should be .............. of the fuel
a. Below the flash point
b. Above the flash point
c. Above the fire point
d. Between the fire and flash point
Ans: c

29. The compression pressure in diesel engine is around
a. 30 Kg/cm2
b. 10 Kg/cm2
c. 20 Kg/cm2
d. 40 Kg/cm2
Ans: a

30. The combustion process in a diesel engine is
a. Constant pressure process
b. Isothermal process
c. Constant volume process
d. Adiabatic process
Ans: a

31. Which type of valve arrangements require the use of rocket arms?
a. H - head
b. T - head
c. I - head
d. L - head
Ans: c

32. The conventional mechanical type fuel pump develops ............. pressure
a. 0.15 Kg/cm2
b. 1.0 Kg/cm2
c. 0.5 Kg/cm2
d. 0.3 Kg/cm2
Ans: b

33. As compression ratio in an engine goes up, the octane requirements of the fuel
a. Goes down
b. Goes up
c. Stay about the same
Ans: b

34. The metering rod is designed to vary the size of which jets
a. High speed jets
b. Accelerating jets
c. Float level jets
d. Idle jets
Ans: a

35. The turbulence in diesel engines ensures to
a. Increase the volumetric efficiency
b. Increase the compression ratio
c. Bring the fuel quickly in contact with the air
d. Increase the specific fuel consumption
Ans: c

36. If compression ratio is increased
a. Thermal efficiency will be increased
b. Volumetric efficiency will be increased
c. Air standard efficiency will be decreased
d. Air standard efficiency will be increased
Ans: d

37. In 'V' type engines the included angle between two banks of cylinders is
a. 450
b. 600
c. 1300
d. 900
Ans: d

38. The duration of the fuel injection at full load in a diesel engine running at 1800 rpm when it has 200 of
crank travel is
a. 1/600 sec
b. 1/640 sec
c. 1/540 sec
d. 1/530 sec
Ans: c

39. Comparing a Four wheel drive with Two wheel drive system either at front or rear and assuming an equal
division of weight between the two axes
a. From the point of view of traction front wheel drive is better than rear wheel drive
b. Front wheel and rear wheel drive are equal
c. Four wheel drive can always give more traction than either rear or front wheel drive
d. Four wheel drive can utilize all the weight of the vehicle only at a particular road friction
Ans: c

40. The range of gear ratios in a vehicle depends on
a. The ratio of engine h.p to laden weight of vehicle
b. Max. engine torque / wt. of vehicle
c. Only on the laden weight of vehicle
d. The power to weight ratio of engine
Ans: b

41. Most of the mopeds in India have capacity of
a. 10 cc
b. 250 cc
c. 50 cc
d. 175 cc
e. 150 cc
Ans: c

42. Which motor cycle has maximum power rating
a. Rajdoot
b. Jawa
c. Yamaha
d. Bullet
Ans: c

43. During a collision the front parts of an automobile are subjected to a deceleration of about ......... at about
50 mphr
a. 100g
b. 1000g
c. 1g
d. 10g
Ans: c

44. Piston displacement is calculated from the
a. Cylinder diameter and length
b. Piston length and diameter
c. Bore and stroke
Ans: c

45. The power used in overcoming friction in the engine is called
a. FHP
b. BHP
c. IHP
Ans: a

46. During combustion the pressure in the cylinder may increase to as much as
a. 50 Kg/cm2
b. 400 Kg/cm2
c. 10 Kg/cm2
Ans: a

47. The size of intake valve is
a. Smaller than that of the exhaust valve
b. Equal to that of the exhaust valve
c. Larger than that of the exhaust valve
d. Not depending upon the size of exhaust valve
Ans: c

48. A negative loop in the P.V diagram of an I.C engine is due to
a. Pre ignition in the engine
b. Suction of air for engine
c. Pre opening of the exhaust valve
d. High pressure in the cylinder
Ans: b

49. Two stoke engine is preferred for small vehicles because
a. Fuel consumption is low
b. Shock and vibrations are less
c. Its size is small
d. It is easy to control
Ans: c

50. Knowing the speed at which an engine is running and the torque it is developing, we can calculate
a. FHP
b. IHP
c. BHP
Ans: a