Almost all car manufacturers have different variants available for the same car.
The car looks the same but will have different features inside and outside.
Maruthi uses L, V, Z alphabets. and their petrol and diesel variants are identified by XI and DI respectively.
Maruti: LXI, VXI, ZXI or LDI, VDI, ZDI

In honda, E, S, SV, V, VX are the variants and AT means automatic transmission and CVT means continuous variable transmission. so if a model says VCVT that means that the variant is and it has a CVT transmission in it.
In Honda cars petrol and diesel is identified by the separate markings iVTEC and iDTEC respectively

These are the different trim levels which is found in maruti suzuki vehicles.
Trim refers to the items that can be added to the interior and exterior of automobile to increase its appeal.
XI denotes petrol engine
LXI is for lower variant cars
VXI includes basic features like ac , power steering  etc
ZXI includes all the high end features  like ABS,Air bags,music player etc.

It is used for differentiating car models in maruti suzuki.
XI -  Petrol car
DI -  Diesel car
L -  Base model
V -  Full option model
Z -  Added features model

LXI is a base model Petrol car.
VXI is a full option Petrol car.
ZXI is a added features Petrol car

The same goes for LDI,  VDI,  ZDI. The only change is that it's a diesel car.


A Twist drill is a drill bit that has a Helical ( screw shaped ) flute cut into it for good swarf removal. It looks like a straight fluted drill bit has been twisted , hence the name.
A stepped drill is a special drill bit generally used to drill thin sections of a material. It is characterized by a series of increasing diameter cutting section which are stepped to specific diameters, allowing the user to drill to whatever diameter they need without having to drill a pilot hole and then change bits to work up to the required diameter of hole. It has a stepped conical profile.

A Burnishing drill generally has straight flutes and multiple stabilizing margin edges with a thinner pilot section at the tip that is followed by an extra set of burnishing margins . This allows very accurate sizing of the hole and the burnishing margins create a very fine finish on the inside of the hole. These drills are extremely precise when you need multiple holes that are very close in size to each other as they tend to be more rigid and do not deform under load like twist drills do.


Stress and pressure are the two important terms used frequently in the science and technology. Though they give same meaning, there are unique characteristics for each term. Pressure is defines as the amount of force applied per unit area.Stress is the amount of force per unit area experienced by a material.Although both have same units of newton/meter^2, they are different only in their context.

Major Differences are:

1. Pressure represents intensity of external forces acting at a point. but stress represent intensity of internal resisting forces develop at a point.

2. Pressure always acts normal to the surface. but but stress may also act either normal or parallel to the surface.

3. Magnitude of pressure at a point in all direction remain same. but magnitude of stress at a point in all the direction are unequal.

4. Pressure can be measured by using measuring device.like pressure gauge. but stress can't be measured directly by using any device.


1.)ANTI DIVE SYSTEM – A system installed with some brakes that uses front fork damping and the front brake assembly to prevent excessive fork compression and to improve handling when brakes are applied.

2.)AUTOMATIC TRANSMISSION – A transmission not using a manually operated clutch.

3.)AXLE – A shaft used to support a part or parts across the frame or forks. e.g., front and rear axles.

4.)BACK BONE FRAME – Frame which uses the engine as a structural member for load carrying.

5.)BEAD – The portion of the tyre which holds it onto the rim.

6.)BEZEL – Piece of metal surrounding head lights, gauges or similar components, sometimes used to hold the glass face of a gauge in the dashboard.

7.)BOOSTER PORT – In a two stroke engine, the port that allows an extra amount of air fuel mixture from the intake port into the combustion chamber.

8.)BRAKE FADE – Loss of braking power, usually caused by excessive heat after repeated brake applications.

9.)BRAKE LINE – Special hydraulic tubing made of steel, plastic or reinforced rubber. Hydraulic lines must be capable of withstanding extreme pressure without deforming.

10.)BRIDGED PORTS – A vertical port division in a two stroke cycle engine cylinder which allows use of a large port without the danger of ring or piston catching.


Stress concentration is the accumulation of stress in a body due to sudden change in its geometry. When there is a sudden change in the geometry of the body due to cracks sharp corners, holes and decrease in the cross section area, then there is an increase in the localised stress near these cracks, sharp corners, holes, and decreased cross section area. The body tends to fail from these places where the stress concentration is more. So to prevent a body from getting failed, the stress concentration should be avoided or reduced.It is also called as stress raisers or stress risers.


The stress concentration in a body happens because of sudden change in the geometry of the body due to cracks, sharp corners, holes, decrease in the cross section area. Due to these irregularities, there is an increase in the intensity of stress in the body.


When a body has stress concentration in it, the chances of its failure increases. The body tends to fail from the place where it is has more concentration of stress. A body has less life that has more irregularities within it. In order to increase the life of the body, the intensity of stress should be reduced.

Stress concentration factor

The stress concentration factor is defined as the ratio of highest stress in the body to the reference stress. It is denoted by Kt.

σmax = Highest stress or maximum stress
σref = Reference stress
The value of stress concentration factor for
(i) A body free from irregularities is 1.
(ii) A body that has maximum irregularities or discontinuity is greater than 1.

Methods to Reduce Stress Concentration

1. There are no of ways to reduce stress concentration in a body and some of these are:
Avoiding sharp corners by providing a fillet radius at the sharp corners. By providing the fillet radius at sharp corners, the cross section area decreases gradually instead of suddenly. And this distributes the stress in the body more uniformly. This is shown in the figure given below.
2. By providing small holes near big hole. If we have an object, that has an internal hole within it. Then the intensity of stress near that hole is more. To avoid this, some smaller holes are created near that hole. This distributes the stress more uniformly than it was before. This is shown in the figure given below.
3. By decreasing the nominal diameter of a threaded object and make it equal to the core diameter. Suppose we have a threaded object. And the intensity of stress at threaded part is more. The chances of object may fail is more at the threaded part. This can be avoided by decreasing the nominal diameter of the shank and make it equal to the core diameter. This will distribute the stress more uniformly in the object with threads.
4. By providing notches or undercut at the sharp corners.


Why do more and more motorcycles now a day have fuel-injection systems rather than carburetor?  

So here is our discussion Carburetor Vs Fuel Injection – Brief Discussion.
The carburetor is one of the most essential mechanical part on a motorcycle and many small engine machines. All engines require a proper mixture of air and fuel for combustion; this vital device known as the carburetor controls the ratio of the fuel/air mixture entering the engine.

The fuel injected system is controlled by a computerized fuel delivery system, while the ECU takes information from various sensors and determines how much fuel the engine receives based on this data. Other sensors deal with RPM, engine temperature, throttle position, and the crankshaft position.

Carburetor Vs Fuel Injection System :

  1. Fuel injector gives a slightly higher engine performance and slightly more efficiency when running at the best fuel-air ratio. Throttle response is also a bit better.
  2. Crucially, most carburetor problems can be fixed easily at the side of the road with an assortment of basic tools. An electronic fuel injection system, though, if it goes wrong, will usually require a new part – and that’s going to cost you. Repair is far more difficult. Today’s modern fuel injection systems require a computer to diagnose the problem.
Advantages of Carburetors:

* Easy to operate and cheap to replace.
* Quick servicing.
* On the go tuning and setting possible
* Can be opened up individually without disturbing the engine.

Disadvantages of Carburetors:

* Diaphragm inside is delicate and can tear which will end up to have it replaced.
* The tuning process needs a big screw driver and has to be done physically.
* There is a certain amount of lag in the process of fuel delivery.
Old technology.
* The air-fuel mixture ratio is not constant.

Advantages of Fuel Injection:

* Fuel delivery is optimum and fuel atomizing allows for complete combustion.
* Increase in fuel efficiency and power output.
* Acceleration sensitivity increases.
* The air fuel mixture can be changed on the go using different fuel maps pre-loaded on the ECU for variable power outputs.

Disadvantages of Fuel Injection:

* Servicing of the FI unit is cumbersome.
* If there is an ECU failure, the bike will seize to work.
* It costs a lot and the service and maintenance is costly as well.
* Producing new Fuel maps needs loads of expertise.
* Procuring new fuel maps is a costly affair.

It is fairly obvious that most automobiles will be changing to fuel injection systems due to the lower emissions. However, unless the cost of these systems decreases significantly then there will still be a massive following that will stick to carburetors. When looking at pure horsepower, the fuel injection system only delivers about 10 extra horsepower at peak.


nuclear power plant is a thermal power station that generates electricity using heat from nuclear reactions. Nuclear reactions take place within a nuclear reactor. Nuclear power plant has a machines which remove heat from the nuclear reactor to operate a steam turbine and generator electricity. Electricity made by nuclear power plants is called nuclear power.
Nuclear power plants use uranium as source of fuel. When the nuclear reactor is on, uranium atoms split into two smaller atoms within the reactor. When uranium atoms split, they give off a large amount of heat energy. This splitting of atoms is called nuclear fission process.
The most popular atoms to nuclear fission process are uranium and plutonium. Those atoms are slightly radioactive in nature. The atoms produced when fuel atoms break apart are strongly radioactive. Today, nuclear fission process occurs only inside the nuclear reactors. In nuclear reactors, nuclear fission process only happens when the nuclear reactors parts are arranged properly. Nuclear power plants turn their reactors off when replacing old nuclear fuel with the new fuel.
Nuclear power plants are usually built near the water sources to remove the heat produced by reactor. Some nuclear power plants use cooling towers to cool the nuclear reactor.
There are various advantages as well disadvantages of having nuclear power plants. Those advantages and limitations are covered below.


  1. Space needed for operating a nuclear power plant is less as compared to other conventional power plants for production of same amount of energy.
  2. A nuclear power plant consumes very small quantity of fuel. Thus fuel transportation cost is less and large fuel storage facilities are not required. Further the nuclear power plants will conserve the fossil fuels such as coal, oil, gas etc. for other energy need.
  3. There is increased reliability of operation.
  4. Nuclear power plants are not effected by the unfavorable weather conditions.
  5. Nuclear power plants are well suited to meet large demands of power requirement. They give better performance at higher load factors of 80 to 90%.
  6. Materials expenditure on metal structures, piping, storage mechanisms is much lower compared to a coal-burning power plant.
  7. It does not need large quantity of water.


  1. Initial cost to set up nuclear power plant is higher as compared to hydro or steam power plant.
  2. Nuclear power plants are not well suited for varying load conditions.
  3. Radioactive wastes if not disposed carefully may have an effect on the health of operators and the population nearby. In a nuclear power plant the major problem faced is the disposal of highly radioactive waste in form of solid, liquid and gas without any injury to the atmosphere. The preservation of radioactive waste for a long duration of time creates many difficulties.
  4. Maintenance cost of the nuclear power plant is high.
  5. Trained people are required to handle nuclear power plants.