Join Our Email Alerts-Subscribe
Important Note:Login & Check Your Email Inbox and Activate Confirmation Link


Enter Your Email :

Copyright Disclaimer:
Section 107 of the Copyright Act Fair Use Contents .
We are forwarding content link(s) from our website to content website & We are not serving any contents.
Main Source:Google.com.All the Content PDF link(s) is/are obtained from GoogleSearch
for the purpose of Education & Teaching Intention. Not for commercial purpose.
Technicalsymposium.com is not liable/responsible for any copyright issues.


Automobile Engineering Materials Free Download





Question 26. How Does The Thermostat Work?

Answer :

When the engine is too cold the thermostat closes the main valve, thus stopping the flow to the radiator. When the engine is too hot, it opens the main valve for normal circulation through the radiator.

Question 27. What Is A Pressure Cap In The Radiator?

Answer :

It is a seal in the radiator that maintains the selected pressure in the cooling system when the engine is hot.

Question 28. Why Does A Compression Engine Use High –octane Fuel?

Answer :

The property of a fuel, which describes how fuel will or will not self-ignite, is called the octane number or just octane. Engines with low compression ratios can use fuels with lower octane number, but high compression engines must use high-octane fuels to avoid self-ignition and knock.

• Question 29. What Is The Use Of Hydrogen In Automobile?

Answer : Low emissions. Essentially no CO or HC in the exhaust as there is no carbon in the fuel. Most exhaust would be H2O and N2 Fuel availability. There are a number of different ways of making hydrogen, including electrolysis of water.

Question 30. What Is The Use Of Natural Gas In Automobiles?

Answer :

High octane number makes it very good S.I engine fuel

Low engine emissions. Less aldehydes than with methanol

Question 31. What Is Pitching In The Suspension System?

Pitching is a rocking action about a transverse axis through the vehicle, parallel to the ground. The front suspension moves out of phase with the rear, experiencing the rocking effect due to pitching.

Question 32. What Do You Mean By Independent Suspension?

Independent suspension refers to the mounting of the wheel on a separate axle, so that road shocks affect only the particular wheel.

Question 33. What Is Pan Hard Rod Or Track Bar?

A pan hard rod is a bar or tube running from one side of the axle to the frame on the other side of the vehicle. It helps the leaf spring in keeping the axle centered under the body during turning a corner.

Question 34. What Is Clutch Drag?

When the clutch is not disengaging fully and provides some difficulty in changing the gears then this defect is called clutch drag.

What happens if gasoline is used in a Diesel engine?Diesel engine will work ?

No, It will not work,as the Compression ratio of Petrol engine is 6 to 10 & that of Diesel engine is 15 to 22. Thus on such high compression, gasoline gets highly compressed & it may blast.

Which Mechanism is used in Automobile gearing system ? Differential mechanism

Why different types of sound are produced in different bikes though they say run on SI engine ?

Engine specifications are different in different manufactures like as Bore Diameter(CC), Ignition timing.Also the exhaust Why entropy decreases with the increase in temperature?

ds=dQ/TEntropy is inversely proportional to the temperature so.as temp. increases,entropy decreases.

1. Define limit, and fit?

fit is defined as the the degree of tightness and looseness between two meeting partw

2. What is the working principle of hydrostatic propeltion system in a tractor?

it depends on pascal law. As the pressure in the system is the same, the force that the fluid gives to the surroundings is therefore equal to pressure x area. In such a way, a small piston feels a small force and a large piston feels a large force

3. WHY THE COLOR OF VEHICLE TYRES ARE ALWAYS BLACK IN COLOUR.

IS THERE ANY THING RELATED WITH HEAT CONDUCTION?

During the process of vulcanisation of rubber to make it sheer resistant to make tyres out of it, a certain proportion of carbon is mixed into it. Without this procedure the tyres will not be able to withstand the friction n stress of the road. This carbon is responsible for giving tyres the characteristic black colour.. When ozone combines with ultraviolet light from the sun, it attacks the tire polymer. To prevent tires from rapidly deteriorating, a sacrificial absorber is used, "carbon black" - which, fittingly, makes tires black

4. What is staring oil grade SAE nos of gear box,in passenger car?

"SAE" STAND "SOCIETY OF AUTOMOTIVE ENGINEERS" (USA).

SAE20W40 :4WHEELER ENGINE,2 WHEELER ENGINE, GEAR BOX &CLUTCH.

SAE40W60 :GEAR BOX OF RWD & 4WD VEHICLE.

5. WHAT IS TRANSVERSE WEIGHT SHIFT DUE TO DRIVE TORQUE?

it is weight of drive torque which is bolted to chassis of the car.

6. Why tractor rear wheel is big then front wheel?

for maximum torque provied

7. What is the range of the engine efficiency for two stroke engine? Why you don't see two stroke engine in car? What are problem with two stroke engine?

the range of two sroke engine is too high compare to the four stroke engine be cause of each revalution one power in two sroke engine . i canot see the 2 sroke engine in car.power loss is more.

8. What is a injecter pressure in heavy viehle?

injecter pressure is 220 kg/cm square

9. WHAT IS THE MEANING OF CC OF ENGINE?

CC stands for Cubic centimeter. CC represents the total volume of an engine cylinder. The engine which has more CC , can produce more power than others.

10. WHAT IS THE DIFFRENCE BITWEEN BS2 & BS3 ENGINE?

IN BS2 there is No catalytic converter to reduce formation of co and HC whereas in BS3 catalytic converter is available to reduce the formation of HC and CO. So less emission of HC and co will take place in BS3

11. What is BHP & How it is measured?

BHP stands for Brake horse power As the name implies it is the braking power required to stall a engine Means horse power required to stop engine rotation

12. By mixing oil in fule of four stroke bike will it damage engine, performance? if not than what happen?

yes, absolutely .. It leads to higher wear and tear in cyclinder liners,piston and damage of the piston .. It even leads to knocking and detonation where abnormal combustion appears and dark smoke and harsh sound will be produced by the engine.

13. does the design & fittings vary on the type of the vehicle engine.. why they use petrol for engines only & vice versa?

No, the type of fitting & design does not vary for automotive segment. Its the same. However, its different in case of aerospace & other sector. In the fittings, usually of hole/shaft one of those is made at the basic size so that it can accommodate the other one.

14. For the purpose of inflating car tyres, spray painting, etc. i.e. say a small workshop, what size of a compressor (CFM) is recommended? It will be generally for a hobby use and not commercial use?

spray painting it is generally used for painting in a very smaller areas of any part and where it is very hard to paint in a brush .... And to improve faster rate of painting,, spray painting r used........usually reciprocating compressor r used but size depends upon requirement...........

15. Explain different between two stroke engine four stroke engine?

In a two stroke engine, for every two rotations of the crank shaft there will be one power stroke.Hence during compression stroke, fuel will be drawn in to the crank case (suction) and during power stroke, burnt fuel will be thrown out through transfer ports (exaust). In a four stroke engine, for every four rotations of the crank shaft there will be one power stroke. Here, suction, compression,power & exaust strokes are seperate as there will be inlet and exaust valves.

16. What is the formula for calculating BHP IN SI UNITS?

Boiler horse power (BHP) is a power unit used for measuring the power output of boilers, widely used in the past, but now confined to North America. The boiler horsepower conversion formula is as follows.

1 Boiler Horsepower = 9,809.5 Watts

17. WHAT IS KING PIN OFFSET?

A geometric parameter which is positive if the kingpin axis intersects the wheel plane at or below ground level, or is negative if the point of intersection is above ground level. Also called scrub radius

18. WHY BIG TYRE USED IN REAR OF VEH? Tractors have big rear tires because ,the larger the surface area of the tractor's wheels touching the ground, the more pulling power you have. Like how tractor pullers have large tires.

Another reason is that the tractor doesn't have to operate at a higher speed to get the same ground speed with larger tires. Gear ratios don't have to be as high b/c of the larger tires.

Question No. 01

What is Automobile Engineering?

Answer: Automobile Engineering is a branch of engineering which deals with designing, manufacturing and operating automobiles. It is a segment of vehicle engineering which deals with motorcycles, buses, trucks, etc. It includes mechanical, electrical, electronic, software and safety elements.

Question No. 02

How will you differentiate between two stroke engine and four stroke engines?

Answer: 2-stroke piston engine has an intake and an exhaust stroke. All air, fuel, and combustion products must be moved in those 2 strokes. A 4-stroke engine has a separate stroke for moving burned (or burning) and unburned mixtures - intake, compression, expansion, and exhaust. Using 4-stroke results in cleaner emissions at the expense of specific power.

Two stroke: For each explosion in cylinder piston moves downwards and upwards (one complete cycle) (Power stroke and Exhaust stroke).

Four stroke: for each explosion in cylinder piston moves down and upwards twice (two complete cycle) (Intake , compression, power, exhaust stroke.)

Four stroke is highly efficient than two stroke. But two stroke is powerful than four stroke.

Question No. 03

What is the range of engine efficiency in case of two stroke engine?

Answer: The two stroke engines have very high range to be compared to the four stroke engines. Because power stroke is generated every two revolution while in four stroke, power stroke is generated every four revolutions.

Definition of Octane number & Cetane number

Answer:

• Octane Number - Octane number is defined as the percentage, by volume, of iso octane in the mixture of iso-octane and h-heptane. It is the measure of rating of SI engine.

• Cetane Number - Cetane number is defined as the percentage, by volume, of n-cetane in the mixture of n-cetane and alpha methyl naphthalene. It is the measure of rating of CI engine.

Question No. 05

What do you understand by CC of engine?

Answer: The meaning of CC is cubic centimeters. It represents the total volume of the engine cylinder. This reflects that the engines with more CC can generate more powers than the other engines. CC can also be related as inversely proportional to the fuel consumption.

Question No. 06

If we use gasoline in diesel engine, what will happen?

Answer: Adding gasoline to the diesel engine may blast off the engine. Compression ratio of the petrol engine is 6 to 10 and diesel engine is 15 to 22. Thus gasoline will get very highly compressed and might result in blast off engine.

Question No. 07

Explain the significance of governor in automobiles?

Answer: Governor is an important component of automobile engine. It is used to regulate the main speed of engine during the variations in loads. With the variations in the load, fuel supply has to be maintained. This task is performed by the governor. In the case of high load on the engine, speed decreases, hence fuel supply has to be increased and similarly when load decreases then the fuel supply has to be decreased.

Question No. 08

What is the use of hydrogen in automobile?

Answer: Low emissions. Essentially no CO or HC in the exhaust as there is no carbon in the fuel. Most exhaust would be H2O and N2 Fuel availability. There are a number of different ways of making hydrogen, including electrolysis of water.

Question No. 09

What is the use of Natural gas in automobiles?

Answer:

• High octane number makes it very good S.I engine fuel

• Low engine emissions. Less aldehydes than with methanol

Question No. 10

What is an automotive differential and how does it work?

Answer: The automotive differential is designed to drive a pair of wheels while allowing them to rotate at different speeds. In vehicles without a differential, such as karts, both driving wheels are forced to rotate at the same speed, usually on a common axle driven by a simple chain-drive mechanism.

Question No. 11

What is the working principle of hydrostatic propulsion system in a tractor?

Answer: It depends on Pascal law. As the pressure in the system is the same, the force that the fluid gives to the surroundings is therefore equal to ‘pressure × area’. In such a way, a small piston feels a small force and a large piston feels a large force

Question No. 12

What is oil grade SAE stands for?

Answer: "SAE" stands for "SOCIETY OF AUTOMOTIVE ENGINEERS" (USA).

Question No. 13

By mixing oil in fuel of four stroke bike will it damage engine, performance? If not than what happen?

Answer: Yes, absolutely. It leads to higher wear and tear in cylinder liners, piston and damage of the piston. It even leads to knocking and detonation where abnormal combustion appears and dark smoke and harsh sound will be produced by the engine.

Question No. 14

Why are car steering wheels round?

Answer:

1. A steering wheel is round so that your hands locate in the same place regardless of the steering wheel's orientation.

2. While turning / steering the car it is ergonomically the best design.

3. Also as design is circle, there are no edges to hit while turning / steering is moving as the circle position remains the same.

4. From Design view, it should be able to give uniform force i.e. torque, by varying the distance from center will vary the torque provided.

Question No. 15

How Trains take turns, though there is no any differential?

Answer: Purpose of the differential is to enable vehicles to take turn, by allowing both the wheel to rotate with different speed. This is required when wheels, like in car, are connected with same axle. Interestingly, wheel in trains are not connected with the axle, they are independent and hence can take turns without ant differential. This is same as how the bullock cart takes turns, without any differential.

Question No. 16

What is the difference between BS2 & BS3 engine?

Answer: IN BS2 there is No catalytic converter to reduce formation of co and HC whereas in BS3 catalytic converter is available to reduce the formation of HC and CO. So less emission of HC and co will take place in BS3

Question No. 17

Why big tyre used in rear of Tractors?

Answer: Tractors have big rear tires because, the larger the surface area of the tractor's wheels touching the ground, the more pulling power you have. Like how tractor pullers have large tires. Another reason is that the tractor doesn't have to operate at a higher speed to get the same ground speed with larger tires. Gear ratios don't have to be as high b/c of the larger tires.

Question No. 18

What will happen if someone adds oil to the fuel of four stroke bike engine?

Answer: This will result in damaging of the engine faster. Adding oil will lead to the higher wear and tear of the cylinder liner, piston and damage to the piston. It will lead to abnormal combustion and knocking and detonation. Dark smoke and abnormal sounds will be generated by the engine. One should not mix oil with the fuel of four stroke engine.

Question No. 19

How air conditioners work in cars?

Answer: Air conditioners are based on the principles of evaporation and condensation and then compression and expansion. The hot air of the car is removed by the process of evaporation and then the condensation of the evaporated air takes places which is then further compressed by the compressor and then finally expanded to us in the form of cold breeze. Somehow, Air conditioning reduces the average of the car, as the energy is required to remove the hot air and then compression and expansion.

Question No. 20

Why entropy decreases with the increase in temperature?

Answer: The relation is ds = dQ/T

Entropy is inversely proportional to the temperature so as temperature increases, entropy decreases.

Question No. 21

What is SAE? Mention the importance of SAE to the automobile domain.

Answer: SAE stands for society of automotive engineers. This society is responsible for developing the standards for the engineering of powered vehicles of all kind. The vehicles may include car, boat, truck and even aircraft. SAE has developed standards for ground vehicles and aerospace vehicles. SAE also encourages students of engineering, technology, science and math’s disciplines. This society has been publishing technical information since 1906.

Question No. 22

How does the thermostat work?

Answer: When the engine is too cold the thermostat closes the main valve, thus stopping the flow to the radiator. When the engine is too hot, it opens the main valve for normal circulation through the radiator.

Question No. 23

Why involute curve used in gear?

Answer:

• It’s smooth to drive the gear.

• In gears contact is only point, this type is curve take the more load than normal one

Question No. 24

What does it mean when your car emits white smoke?

Answer: White smoke is a sign of a coolant leak as is milky brownish oil. This could be due to bad head gasket or cracked block. Burning oil smoke is usually more bluish in color. White smoke is usually associated with a coolant leak, but burning oil can also look like white smoke

Question No. 25

What happens if gasoline is used in a Diesel engine? Diesel engine will work?

Answer: No, it will not work, as the Compression ratio of Petrol engine is 6 to 10 & that of Diesel engine is 15 to 22. Thus on such high compression, gasoline gets highly compressed & it may blast.

• What happens if gasoline is used in a Diesel engine?Diesel engine will work ?

No, It will not work,as the Compression ratio of Petrol engine is 6 to 10 & that of Diesel engine is 15 to 22. Thus on such high compression, gasoline gets highly compressed & it may blast.

• Which Mechanism is used in Automobile gearing system

Differential mechanism

• Why different types of sound are produced in different bikes though they say run on SI engine

Engine specifications are different in different manufactures like as Bore Diameter(CC), Ignition timing.Also the exhaust passage take more responsible for sound.

• Why entropy decreases with the increase in temperature?

ds=dQ/TEntropy is inversely proportional to the temperature so.as temp. increases,entropy decreases.

• 1 hp how much watt?

746.2Watt

o How to calculate bearing number to diameter of the inner and outer

Divide the shaft diameter size by 5, it will give last two digitof the bearing no. and according to type of load we have tochose the type of bearing and that will give prior no. ofthe bearing.

o Explain Bicycle rear wheel Sprocket working?

Rear wheel sprocket works under the principle of ratchet and pawl.

o Definition of Octane number & Cetane number

Octane No.- Octane number is defined as the percentage, by volume, of iso octane in the mixture of iso octane and h-heptane. It is the measure of rating of SI engine.

Cetane No.- Cetane number is defined as the percentage, by volume, of n-cetane in the mixture of n-cetane and alpha methyl naphthalene. It is the measure of rating of CI engine.

o Poisons ratio is higher in (rubber/steel/wood)

When a material is compressed in one direction, it usuallytends to expand in the other two directions perpendicular tothe direction of compression. This phenomenon is called thePoisson effect. Poisson’s ratio is a measure of the Poisson effect.

For rubber = 0.5

For steel = 0.288

For wood < 0.2

Thus Poisson’s ratio is higher in RUBBER.

o The Fatigue life of a part can be improved by ?

Improving the surface finish by Polishing & providing residual stress by Shot peening.

Source: Contents are provided by Technicalsymposium Google Group Members. Disclaimer: All the above contents are provided by technicalsymposium.com Google Group members. Further, this content is not intended to be used for commercial purpose. Technicalsymposium.com is not liable/responsible for any copyright issues.



Download-Technical Interview Q & A PDF


Free Technical Interview Notes PDF-Download



Technicalsymposium.com- Fresher Jobs & All Study Notes-Free Download










Technicalsymposium.com-Free Live Support-Chat with Our Experts

Official Contact: +91-9245556793 (Whatsapp Message / SMS / Voice Call)


Our Expert team is ready to answer all your questions immediately-Feel free to speak in Tamil/English.

(Example:Events info/Lecture Notes/Off-Campus & All Jobs/Projects & All education information)

Working hrs (IST): (Morning: 10:00AM-3:00 PM) and (Evening:5:00 PM to 10:00 PM)

All Latest Question & Answer Page (FAQ)-Click here