Mechanical Engineering

Composite is consist of two phase, one is Reinforcing phase and other is Matrix. Reinforcing phase is like fibers, particles, flakes. Matrix  is a continuous phase. Example of composite: Concrete reinforced with steel, epoxy reinforced with fibers. Naturally found : Bone-salt plates made of calcium and phosphate ions reinforcement soft collagen. Some advanced composites are: graphite/epoxy, Kevlar/epoxy, fiber glass etc.

A Composite Material is a material made from two or more constituent materials with significantly different physical or chemical properties that, when combined, produce a material with characteristics different from the individual components. Composite Material was introduced long time ago. But was in different form. Bricks were made by using clay and straw. It was ancient use  of composite material. But now-a-days composite materials example: carbon, glass, epoxy etc.

The energy required to break down a nucleus into its component nucleons is called the   nuclear binding energy . 63 Cu + Energy   29 p +  + 34 n o Nuclear binding energies are usually expressed in terms of kJ/mole of nuclei or MeV's/nucleon. To convert the binding energy to   MeV  (megaelectron volts) per   nucleon   we will employ the conversion factor for converting   joules   into   MeV  (1  MeV  = 1.602 x 10 - 13 J ) and the number of   nucleons   (protons and neutrons) which make up the nucleus.

These process are very simple.  All three devices work on the basis of heat flow. In a heat engine, heat is transferred from a higher temperature level called source to a lower temperature level called sink. Work is obtained during this process. A refrigerator is a reversed heat engine. Heat is transferred from the lower temperature level to higher temperature by applying external work to maintain the temperature below atmospheric temperature. A heat pump is similar to a refrigerator. The only point of difference between the two is of the operating temperatures. The working temperatures in a refrigerator are of the colder level and atmosphere, whereas working temperatures in heat pump are of hotter level and atmosphere.

The refrigeration cycle is a normal process consist of, Compression, Condensation, Expansion,Evaporation .The process are given below: Refrigeration Cycle    The compressor constricts the refrigerant vapor, raising its   pressure, and pushes it into the coils on the outside of the   refrigerator. When the hot gas in the coils meets the cooler air temperature of the kitchen , it becomes a liquid. Now in liquid form at high pressure, the refrigerant cools as it flows into the coils inside the freezer and the fridge. The refrigerant absorbs the heat inside the fridge, cooling down the air. Last, the refrigerant evaporates to a gas, then flows back to the compressor, where the cycle starts all over.

 Though there have no clear data about the question answer. It can assume, there are about 10 billion galaxies in the observable universe! The number of stars in a galaxy varies, but assuming an average of  100 billion  stars per galaxy means that there are about 1,000,000,000,000,000,000,000 (that's 1 billion trillion) stars in the observable universe! Stars are very beautiful in the sky. They glitters in the sky all time. But we can notice it only night. The size of this stars are very big. They are bigger than world.

Turbines using the impulse action of water are the best ones. No it’s not like that reaction turbines are more efficient, when all of this was happening, James B. Francis, an American civil engineer comes up with his turbine called Francis turbine. What’s different he is doing!!! He is just mixing them up. The good’s of both the impulse and reaction turbine, say water enters the turbine radially and exits axially. But that’s not a secret to his turbine efficiency. The magic lies in his amazing design of blades, these blades rotate using both reaction and impulse force of water flowing through them. The ability of francis turbine to use both the kinetic and potential energy to produce power, shorts out a major problem of water head availability as it could be used efficiently for head as low as 50m to as high as 400m and also for a wide range of flow rates which could be as low as 10 meter-cube per second to as high as 700 meter-cube per second. Francis Turbine BA