which is better 'petrol car or diesel car' ?

India, being a developing country, has huge population of vehicle owners and this figure is increasing rapidly. Though selection of most suitable car depends on various parameters like cost, average, size,design etc. but there is one thing that always bothers the buyer which is 'Diesel car or petrol car'. Though this is a never ending debate but still based on some parameters one can prefer a type. These parameters are- use for which car is required (i.e. domestic or commercial use), how frequently do you use the car or how much you are willing to pay etc. They are described below.

 

1. Cost of the car : The diesel variant of cars cost more than the petrol variant. For cars which cost less than 10 Lakhs, the showroom price between diesel and petrol variants differs from 1 to 1.5 Lakhs. The difference in the on-road price of petrol and diesel car variants will be even more. This is because the cost of registration for the diesel car is more than that of the Petrol car; the difference is about 1 to 3% depending on the cost of the vehicle and the State where it is purchased.
2. Average or mileage : The mileage of diesel engine is more than that of a Petrol engine. A diesel engine does not need a spark plug and thus has higher compression. This makes the diesel engine utilize more fuel as compared to a petrol engine. The better mileage of a diesel engine makes it easy to cover the extra cost of the car paid initially, but with increasing cost of cars, the time required to recover this cost has increased.
3. Cost of fuel : At present, per liter cost of diesel is about Rs. 9 less than that of petrol. After the partial deregulation of diesel price in 2013, there has been a gradual fall in the difference from 21 rupees in 2013 to approx. 10 rupees in 2014. So there is no concrete base to say that there will be a price difference between the two in the forthcoming years as well.
4. Smooth drive : Diesel engines are more powerful than petrol engines. They also have a higher torque and hence they give a smoother drive. On the other hand, the harshness, noise, and vibrations in diesel driven cars are way higher than that of a petrol-driven car.
5. Maintenance : The maintenance cost of diesel cars is higher than petrol cars. This is because consumables like engine oil and spares used in diesel vehicles are more expensive.  The resale value of a used diesel car is higher than that of a petrol car. However, the life of a petrol engine is more than a diesel engine.                                                                                                                                                                                                                                           So now that you have the pros and cons of both these vehicles, hope you can choose the one that suits your requirements better.

Are microwaves as unhealthy as we are told?

A microwave oven, commonly referred to as a microwave, is a kitchen appliance that heats and cooks food by exposing it to microwave radiation in the electromagnetic spectrum. Percy Spencer (An american physicist and radio engineer) is generally credited with inventing the modern microwave oven after World War II from radar technology developed during the war. Since the time of its invention people are having misconception about it due to the simple fact that it uses radiation to cook the food. So in this article I will take a look at some of the facts behind the most common microwave concerns. Do they leave radiations in the food after cooking? Do they leak radiations? Do they destroy nutrients in the food? Do they denature proteins and make food toxic to our bodies? First though, let us start with basics, what are microwave radiations and how does the microwave oven work?

What are the microwave radiations?

         Microwaves are a form of "electromagnetic" radiation; that is, they are waves of electrical and magnetic energy moving together through space. Electromagnetic radiation ranges from the energetic x-rays to the less energetic radio frequency waves used in broadcasting. Microwaves fall into the radio frequency band of electromagnetic radiation. Microwaves should not be confused with x-rays, which are more powerful. The Em wave spectrum looks something like:

Microwaves have three characteristics that allow them to be used in cooking:

•  they are reflected by metal
•  they pass through glass, paper, plastic, and similar materials
•  they are absorbed by foods.

How do microwave ovens work?

              Microwaves are produced inside the oven by an electron tube called a magnetron. The microwaves are reflected within the metal interior of the oven where they are absorbed by food. Microwaves cause water molecules in food to vibrate, producing heat that cooks the food. That's why foods high in water content, like fresh vegetables, can be cooked more quickly than other foods. The microwave energy is changed to heat as it is absorbed by food, and does not make food “radioactive” or "contaminated." Working can be understood by following line diagram:

Although heat is produced directly in the food, microwave ovens do not cook food from the "inside out." When thick foods are cooked, the outer layers are heated and cooked primarily by microwaves while the inside is cooked mainly by the conduction of heat from the hot outer layers.Microwave cooking can be more energy efficient than conventional cooking because foods cook faster and the energy heats only the food, not the whole oven compartment. Microwave cooking does not reduce the nutritional value of foods any more than conventional cooking. In fact, foods cooked in a microwave oven may keep more of their vitamins and minerals, because microwave ovens can cook more quickly and without adding water.

Do microwaves leak radiation?

           One concern many people have about microwave ovens is the simple fact that they emit, well, microwaves. Hasn’t exposure to microwave radiation been linked to cancer and infertility? Evidence is mixed; most published research concludes that low-level microwave exposure doesn’t present a significant risk to human health. Even if it did, this is only an issue if the microwaves inside the microwave somehow escape the microwave and encounter your body, which is unlikely.The FDA(U.S. food and drug administration) requires that microwaves emit no more than 5 mW/cm2 of radiation at a distance of 2 inches from the microwave. They also point out that microwave radiation dissipates rapidly as you move away from the source, so a measurement taken 20 inches from the microwave would be about 1/100 of the measurement taken at 2 inches. This is good news, because it means that to avoid radiation from your microwave, all you have to do is step away from it while your food is heating.

            Honestly, just don’t press your face up against the door of the microwave while your food is cooking, and step a few feet away if you can. If you’re going to be concerned about exposure to microwave radiation, you’d probably be better off getting rid of your cellphone than your microwave oven.

Do microwaves destroy nutrients and make proteins toxic?

                 As far as vitamins, minerals, antioxidants, and plant phenols, retention does not appear to depend on cooking method. Levels of nutrient retention were sometimes higher in microwaved food, and sometimes lower, depending on time, temperature, and amount of water used in the cooking process.In general, nutrients are lost from food during any type of cooking, and more nutrients are lost when the temperature is higher or the food is cooked for longer. Water soluble vitamins are readily leached into cooking liquid (no surprise there), so boiling food tends to result in greater nutrient losses than microwaving it with a small amount of water (unless you drink the water you boiled the food in, in which case you’d still be getting most of the nutrients).

Don’t fear the microwave!

                 In conclusion, microwaves aren’t as scary as some people make them out to be. Yes, they’re another source of microwave radiation in your home, but the levels are extremely low, and can be almost entirely avoided by simply stepping away while your food is heating. And compared with microwave radiation from other devices (particularly cell phones), radiation from your microwave oven is negligible.

Additionally, there’s no evidence that microwaves adversely affect the nutrient profile of foods. Because microwaves are a relatively new device, I prefer to think of them as “guilty until proven innocent” rather than the other way around, but given what we know about EM radiation and its effects on food molecules, there isn’t really a mechanism by which microwaves could destroy nutrients other than heat. And heat, of course, is an issue regardless of cooking method!

 Tips on Safe Microwave Oven Operation

• Follow the manufacturer's instruction manual for recommended operating procedures and safety precautions for your oven model.
• Don't operate an oven if the door does not close firmly or is bent, warped, or otherwise damaged.
• Never operate an oven if you have reason to believe it will continue to operate with the door open.
• As an added safety precaution, don't stand directly against an oven (and don't allow children to do this) for long periods of time while it is operating.
• Users should not heat water or liquids in the microwave oven for excessive amounts of time.

DISCLAIMER:

       While I strive to provide as accurate and balanced information as possible on my Blog, This blog cannot guarantee its accuracy or completeness because there is always more research to do, and more up-to-date research studies emerging -- and this is especially the case regarding research on the health and environmental effects of plastics. Therefore I do not hold any responsibility for the damage caused by using this information

Recycling symbol on plastic bottles and containers

Have you ever wondered what the recycling symbols (Those made of chasing arrows and a number inside it) mean at the bottom of plastic bottles and containers? Did you know that, while the use of all plastics should be limited if at all possible, some are safer than others?So let us learn a little bit about the various plastics we use and drink/eat from every single day, and what impact they have not only on us, but also the environment.

In 1988, to assist recycling of disposable items, the Plastic Bottle Institute of the Society of the Plastics Industry devised a now-familiar scheme to mark plastic bottles by plastic type. A plastic container using this scheme is marked with a triangle of three "chasing arrows", which encloses a number giving the plastic type:

-[PETE Or PET] - Polyethylene terephthalate. PET is the most well known member of the polyester family of plastic polymers. It is usually clear and used to make soda and water bottles. Some consider it safe, but this plastic is known to allow bacteria to accumulate.

• It’s found mostly in soda bottles, water bottles, beer bottles, salad dressing containers, detergent and cleaner containers etc.
  
• It is recycled into tote bags, furniture, carpet, paneling, fiber, and polar fleece.

HDPE

 

-[HDPE] - high-density polyethylene. Polyethylene are the most widely used family of plastics in the world. This plastic is one of the 3 plastics considered to be safe, and has a lower risk of leaching.

• It’s found mostly in milk jugs, household cleaner containers, juice bottles, shampoo bottles, cereal box liners, detergent bottles, motor oil bottles, yogurt tubs, and butter tubs.ilk jugs, detergent bottles, juice bottles, butter tubs, and toiletries bottles are made of this. 
• It is recycled into pens, recycling containers, picnic tables, lumber, benches, fencing, and detergent bottles, to name a few.

 

-[PVC] - Poly vinyl chloride.Long the second most widely used plastic resin in the world (after polyethylene), PVC (or vinyl) use has decreased because of serious health and environmental pollution issues associated with its manufacture, use and disposal -- it's whole life cycle is toxic. But it is still popular and in common use because of its cost-effective versatility.

• It’s found in shampoo bottles, clear food packaging, cooking oil bottles, medical equipment, piping, and windows. It is also used to make food wrap, plumbing pipes, and detergent bottles.
• This plastic is recycled into paneling, flooring, speed bumps, decks, and roadway gutters.
• These plastics used to, and still may, contain phthalates, which are linked to numerous health issues ranging from developmental problems to miscarriages. They also contain DEHA (Diethylhydroxylamine), which can be carcinogenic with long-term exposure. DEHA has also been linked to loss of bone mass and liver problems. Don’t cook with or burn this plastic.

-[LDPE] -  low-density polyethylene. They are another version of polythene. Being relatively stable they are considered a little safer for food or drink purpose. Also they are easy to process hence are popular for recycling.

• Low density polyethylene is most found in squeezable bottles, shopping bags, clothing, carpet, frozen food, bread bags, and some food wraps. This rests among the recycling symbols considered to be safe.
• This plastic is recycled into compost bins, paneling, trash can liners and cans, floor tiles, and shipping envelopes.

-[PP] - polypropylene.  Polypropylene is used for similar applications as polyethylenes, but is generally stiffer and more heat resistant - so is often used for containers filled with hot food.

• It is also one of the safer plastics to look for.It is typically found in yogurt containers, ketchup bottles, syrup bottles, and medicine bottles.
• Polypropylene is recycled into brooms, auto battery cases, bins, pallets, signal lights, ice scrapers, and bicycle racks.

-[PS] - polystyrene. Polystyrene is Styrofoam, which is notorious for being difficult to recycle, and thus, bad for the environment. This kind of plastic also poses a health risk, leaching potentially toxic chemicals, especially when heated. 

• It is found in compact disc cases, egg cartons, meat trays, and disposable plates and cups.
• It is recycled into egg cartons, vents, foam packing, and insulation.

-[OTHER] -All of the plastic resins that don’t fit into the other categories are placed in the number 7 category. It’s a mix bag of plastics that includes polycarbonate, which contains the toxic bisphenol-A (BPA). These plastics should be avoided due to possibly containing hormone disruptors like BPA, which has been linked to infertility, hyperactivity, reproductive problems, and other health issues.

• It is found in sunglasses, iPod cases, computer cases, nylon, 3- and 5-gallon water bottles, and bullet-proof materials.
• It is recycled into plastic lumber and other custom-made products.

The Bottom Line: Which Recycling Numbers to Avoid, Which are ‘Safest’
In the end, it’s really best to avoid using all plastics if you’re able. But at the very least:

• Avoid recycling symbols 3, 6, and 7. While Number 1 is considered safe, it is also best to avoid this plastic
• Look for symbols 2, 4, and 5, as these plastics are considered to be safest. These are the plastics to look for in terms of human and animal consumption.

DISCLAIMER:

While I strive to provide as accurate and balanced information as possible on my Blog, This blog cannot guarantee its accuracy or completeness because there is always more research to do, and more up-to-date research studies emerging -- and this is especially the case regarding research on the health and environmental effects of plastics. Therefore I do not hold any responsibility for the damage caused by using this information.

"Why an another blog : Motto behind it"

Image Courtesy: Google/trijsolutions.com

                             Knowledge is the key to successful future

 Today you see so much material is available on Internet about each and every thing. Whatever you need to know just you Google it and you will find hundreds of links so there is no question of lack of resources. But suppose if you are a reading enthusiast/ knowledge seeker , who has not been instructed by someone to read something or to learn something but you are reading for your own interest by your own then obviously your chances to learn something new will reduce because whatever you will type will be somehow known to you. So just to cater the need of people, who are mechanical enthusiasts, I have created this blog called Gyrowave. Here on a regular basis I will be posting something new and really interesting like- new technologies in mechanical and automobile field, various interesting principles governing our daily life activities etc. Also on my blog I will be posting a challenging question daily at 9:00 PM. The name of first person to answer the question will be placed on the blog. And last but not the least, this blog is not only for mechanical students but it is for all the people who are attracted to the beauty of mechanisms and machines.

Now about me, I am an undergraduate student currently pursuing my B.tech from Malaviya National Institute of technology, Jaipur in Mechanical engineering. From my childhood, this field of mechanical engineering has always astonished me, that's why I chose it as my subject for under graduation and also that is the reason why I chose it for blogging.

Thanks for reading.