Useful answers

Bike-engined car:

           A bike-engined car is a small or light weight car that is powered by an engine that was designed for use in a motorcycle. The advantage for car builders is that small car engines in high states of tune are relatively rare whereas large motorcycle engines are frequently designed for high specific outputs. The drawbacks of using bike engines in cars is the lack of reverse gear, lack of low end torque (both characteristics making parking difficult) and that the engines get a short lifespan since they have to pull more weight than they were designed for. Most of these cars use the sequential gearbox from the motorcycle, allowing for faster shifting than a traditional automotive gearbox. 

 

 

BMW Info

Bayerische Motoren Werke:

First BMW Motor:
           
         BMW began building motorcycle engines and then motorcycles after World War I. Its motorcycle brand is now known as BMW Motorrad. Their first successful motorcycle, after the failed Helios and Flink, was the "R32" in 1923. This had a "boxer" twin engine, in which a cylinder projects into the air-flow from each side of the machine. Apart from their single cylinder models (basically to the same pattern), all their motorcycles used this distinctive layout until the early 1980s. Many BMWs are still produced in this layout, which is designated the R Series. 

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What material used in bullet?

Prabaharan ans: 
Bullets are made of a variety of materials. Lead or a lead alloy (typically containing antimony) is the traditional bullet core material. Traditional bullet jackets are made of copper or gilding metal, an alloy of copper and zinc. There are many other materials that are used in bullets today, including aluminum, bismuth, bronze, copper, plastics, rubber, steel, tin, and tungsten.

Bullet lubricants include waxes (traditionally carnauba wax made from the carnauba palm), oils, and molybdenum disulfide (moly). Modern wax and oil formulas are generally not made public. Moly is a recent innovation; this naturally occurring mineral sticks to metal on contact. The bullet making process can also use grease and oils to lubricate the bullet during machining and pressing steps. This lubrication prevents damage to the bullet or the machinery by allowing the bullet and machinery to move against each other without sticking. Solvents are used to remove grease and oil from the bullet afterward.

What material used in bullet shield?


What material used for thermal insulation in flask?


Why  Calorific value vary in fuels?

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Propane:liquefied petroleum gas (LPG)

       Propane or liquefied petroleum gas (LPG) is a clean-burning fossil fuel that can be used to power internal combustion engines. LPG-fueled vehicles produce fewer toxic and smog-forming air pollutants. LPG is usually less expensive than gasoline, and most LPG used in U.S. comes from domestic sources.
No LPG-fueled light-duty passenger cars or trucks have been produced commercially in the U.S. since the 2004 model year, but gasoline and diesel vehicles can be retrofitted to run on LPG in addition to conventional fuel. The LPG is stored in high-pressure fuel tanks, so separate fuel systems are needed in vehicles powered by both LPG and a conventional fuel such as gasoline.

 Advantages:      

• Fewer toxic and smog-forming air pollutants
• 85% of LPG used in U.S. comes from domestic sources
• Less expensive than gasoline

 Disadvantages:

• No new passenger cars or trucks commercially available (vehicles can be retrofitted for LPG)
• Less readily available than gasoline & diesel
• Fewer miles on a tank of fuel

Hydrogen Fuel:
Hydrogen (H₂) is being aggressively explored as a fuel for passenger vehicles. It can be used in fuel cells to power electric motors or burned in internal combustion engines (ICEs).
It is an environmentally friendly fuel that has the potential to dramatically reduce our dependence on imported oil, but several significant challenges must be overcome before it can be widely used.

Benefits

Produced Domestically. Hydrogen can be produced domestically from several sources, reducing our dependence on petroleum imports.
Environmentally Friendly. Hydrogen produces no air pollutants or greenhouse gases when used in fuel cells; it produces only nitrogen oxides (NOx) when burned in ICEs.

Challenges

Fuel Cost & Availability. Hydrogen is currently expensive to produce and is only available at a handful of locations, mostly in California.
Vehicle Cost & Availability. Fuel cell vehicles are currently far too expensive for most consumers to afford, and they are only available to a few demonstration fleets.
Onboard Fuel Storage. Hydrogen contains much less energy than gasoline or diesel on a per-volume basis, making it difficult for hydrogen vehicles to go as far as gasoline vehicles between fillups—about 300 miles. Technology is improving, but the onboard hydrogen storage systems do not yet meet size, wieght, and cost goals for commercialization.
Other challenges include fuel cell performance, customer acceptance, and hydrogen transport and bulk storage.

Ethanol is an alcohol-based fuel made by fermenting and distilling starch crops, such as corn. It can also be made from "cellulosic biomass" such as trees and grasses. The use of ethanol can reduce our dependence upon foreign oil and reduce greenhouse gas emissions.

E10 (gasohol)

E10 (also called “gasohol”) is a blend of 10% ethanol and 90% gasoline sold in many parts of the country. All auto manufacturers approve the use of blends of 10% ethanol or less in their gasoline vehicles. However, vehicles will typically go 3–4% fewer miles per gallon on E10 than on straight gasoline.¹

E85

E85, a blend of 85% ethanol and 15% gasoline, can be used in flexible fuel vehicles (FFVs), which are specially designed to run on gasoline, E85, or any mixture of the two. FFVs are offered by several vehicle manufacturers. To determine if your vehicle can use E85, consult your owner’s manual or check the inside of your car's fuel filler door for an identification sticker.
Cost. Cost varies regionally. It is cheaper than gasoline in some areas, such as the Midwest, and more expensive in others.
Availability. More than two thousand filling stations in the U.S. sell E85, and that number is increasing rapidly. Visit the Alternative Fueling Station Locator for locations of service stations selling E85.
Performance. No noticeable difference in vehicle performance when E85 is used.
MPG. FFVs operating on E85 usually experience a 25–30% drop in miles per gallon due to ethanol’s lower energy content.²

Advantages of E85:

• Domestically produced, reducing use of imported petroleum
• Lower emissions of air pollutants
• More resistant to engine knock
• Added vehicle cost is very small

Disadvantages of E85:

• Can only be used in flex-fuel vehicles
• Lower energy content, resulting in fewer miles per gallon
• Limited availability
• Currently expensive to produce

Diesel Vehicles

Diesel vehicles may be making a comeback. Diesel engines are more powerful and fuel-efficient than similar-sized gasoline engines (about 30-35% more fuel efficient). Plus, today's diesel vehicles are much improved over diesels of the past.

Better Performance

Improved fuel injection and electronic engine control technologies have

• Increased power
• Improved acceleration
• Increased efficiency

New engine designs, along with noise- and vibration-damping technologies, have made them quieter and smoother. Cold-weather starting has been improved also.

Cleaner

Today's diesels must meet the same emissions standards as gasoline vehicles. Advances in engine technologies, ultra-low sulfur diesel fuel, and improved exhaust treatment have made this possible.
Although emissions of particulates and smog-forming nitrogen oxides (NOx) are still relatively high, new "clean" diesel fuels, such as ultra-low sulfur diesel and biodiesel, and advances in emission control technologies will reduce these pollutants also.