Why even matter repeatedly today? KR IRS On Sat, 22 Jul 2023 at 18:35, gopala krishnan <[email protected]> wrote:
> *CULTURAL QA 07-2023-23* > > > > Dear friends, > > As per the advice of a very senior member I will not be responding to > responses by Sri Rajaram and Sri APS Mani. Of course if they abuse I will > be writing back > > Gopalakrishnan 23-7-23 > > Q1 Why do aeroplanes use kerosene (parafin) as fuel? > > A1 Rebecca Williams, Experience in Aviation Jul 13 > > *Kerosene is a type of aviation fuel that is based on refined petroleum. > It is also known as jet fuel, aviation turbine fuel, or after*. There are > different grades of kerosene, such as Jet A, Jet A-1, Jet B, and JP-8, > which have slightly different specifications and properties. *They all > share some common characteristics that make them suitable for airplane > engines. Some of the advantages of kerosene are:* > > Kerosene has a high energy density, meaning that it contains a lot of > energy per unit of mass or volume. This allows airplanes to carry more fuel > and fly longer distances without refueling. Kerosene has an energy density > of about 43 MJ/kg or 34 MJ/L, compared to gasoline’s 46 MJ/kg or 32 MJ/L. > > Kerosene has a low freezing point, meaning that it remains liquid at very > low temperatures. This is important for airplanes that fly at high > altitudes, where the ambient temperature can drop below -50°C. Kerosene has > a freezing point of about -47°C, compared to gasoline’s -60°C. > > Kerosene has a high flash point, meaning that it requires a high > temperature to ignite. This makes it safer to transport and handle than > more flammable fuels, such as gasoline or diesel. Kerosene has a flash > point of about 38°C, compared to gasoline’s -43°C. > > Kerosene has a low viscosity, meaning that it flows easily and does not > clog up the engine’s fuel system. This is important for airplanes that have > complex and sensitive fuel pumps, injectors, and filters. Kerosene has a > viscosity of about 3 cSt at 20°C, compared to gasoline’s 0.5 cSt or > diesel’s 4 cSt. > > Kerosene is compatible with most airplane engines, whether they are piston > engines or turbine engines. Piston engines can run on kerosene with minor > modifications, such as higher compression ratios and fuel injection > systems. Turbine engines are designed to run on kerosene, as they use > high-pressure air and fuel to create thrust > > My note- paraffin oil is available in medical shops under prescription, > applied to bottom of the foot for pain under the foot. Prescribed by > Neuro doctors > > Q2 Why do some metals corrode when exposed to air? > > A2 Erika Fernandez,Bike Lover12h > > *Some metals corrode when exposed to air because they have a tendency to > lose electrons and form positive ions*. This tendency is called the > activity of the metal and it depends on the position of the metal in the > reactivity series. The reactivity series is a list of metals arranged in > order of their decreasing activity, from the most reactive to the least > reactive. The most reactive metals are at the top of the list and they can > easily lose electrons and form positive ions. The least reactive metals are > at the bottom of the list and they can resist losing electrons and forming > positive ions. > > When a metal is exposed to air, it can react with oxygen or water vapor > in the air to form metal oxides or hydroxides. *For example, iron reacts > with oxygen to form iron oxide, commonly known as rust.* This reaction is > accelerated by the presence of water or salt, which act as electrolytes and > allow the flow of electrons between different parts of the metal surface. > The iron atoms lose electrons and become iron ions, while the oxygen atoms > gain electrons and become oxide ions. The iron ions and oxide ions combine > to form iron oxide, which is a brown flaky material that does not protect > the metal from further corrosion. > > Some metals can also react with carbon dioxide or sulfur dioxide in the > air to form metal carbonates or sulfates. For example, *copper reacts > with carbon dioxide and water to form copper carbonate, which is a > greenish-blue substance that covers the surface of copper objects such as > statues or pipes. This reaction is slow and does not damage the metal > significantly.* > > Some metals do not corrode when exposed to air because they have a low > activity and can form a thin layer of metal oxide on their surface that > acts as a barrier and prevents further reaction with oxygen or water. For > example, *aluminum reacts with oxygen to form aluminum oxide, which is a > hard and transparent substance that adheres tightly to the metal surface. > This layer protects the aluminum from further corrosion and makes it > resistant to weathering.* > > Also few metals do not corrode when exposed to air at all because they > have a very low activity and do not react with oxygen or water under normal > conditions. For example, gold and platinum do not oxidize in air and remain > shiny and unaltered for a long time. > > My note-Informative answer told in simplest language > > Q3 Have you ever gained respect for somebody instantly? > > A3 Gurmeet Bishnoi, Lives in Berlin (2023–present)2y > > Do you know who is she -She is Dr. Raisa Ansari - She has PhD in physics > > *Raisa, a Master in Physics and PhD from Devi Ahalya Bai University of > Indore, received an offer to do research from Belgium*. But her research > head did not sign her recommendation letter. Her viva was not done until > two years after the thesis was submitted and then *she could get viva > after administrative intervention.* > > Raisa has done research from IISER (Indian Institute of Science Education > and Research), Kolkata on fellowship of CSIR (Council of Scientific and > Industrial Research). Due to a sign Raisa could not go to Belgium to > research. > > *Due to a sign and not any support, she is selling fruits. We all feel > sorry that such educated woman has to sell fruits but there is a fact that > she didn't give up.* > > She didn't compromise her honor. If her guide didn't sign her document, > still she started working by herself and earning for her. She is not > ashamed to do such work and I do feel proud for her honor. > > Q4 Does Airtel still have a priority network for postpaid > customers? > > A4 Gopala Krishnan, Former Asst General Manager, Retired at > Bharat Sanchar Nigam Limited (BSNL)Just now > > I am a post paid subscriber of Airtel. My bill comes under one family one > bill scheme now. Under this scheme all the existing connections become post > paid. > > Before I got my B S N L SIM In Chennai which was in high demand during > 2004 end, I had to purchase Airtel SIM. It was prepaid. At one time there > was a campaign to convert prepaid to post-paid. Paying a deposit I was > given ISD facility in prepaid which still continues. > > When there is a tower failure, automatically the customers are connected > to the nearest next tower. Depending on signal strength, you phone may/may > not function. > > No priority in any way for post paid customers in any manner in Chennai > > Q5 Why do airplanes prefer to fly over the ocean? > > A5 Mayfair Jets. Aviation Enthusiast May 15 > > *Have you ever wondered why your flight path curved over the ocean, even > though it seemed out of the way? It's all about efficiency and safety, > friends! Let's dive into this fascinating aspect of air travel.* > > *Aircraft often follow what's known as the "Great Circle" route. This > might look curved on a flat map, but it's actually the shortest distance > between two points on a globe*. When you're traveling thousands of miles, > following a Great Circle route saves time and fuel, even if it seems to > curve oddly over the ocean. > > Over the ocean, air tends to be less turbulent compared to over land, > thanks to the uniform temperature of the sea surface. > > This means less bouncing around for you and your in-flight drink! So, the > next time you're on a plane, *look out of the window and appreciate the > ocean beneath - it's not just a pretty view, it's part of smart and > efficient aviation.* > > *All the above QA are from Quora website on 23 -07-2023.* > > *Quora answers need not be 100% correct answers.* > > *Compiled and posted by R. Gopala Krishnan, 79, on 23-07-2023.* > > > > -- You received this message because you are subscribed to the Google Groups "Thatha_Patty" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/thatha_patty/CAL5XZoqXiy7_GT2LcXnqBfx5hDLPynLkT-YvgbApekTeKEKrBg%40mail.gmail.com.
