Machine Parts

The increase of pressure on a gas decrease of its volume.    This also increases its temperature. In naturally temperature or heat is nothing or nor less than speed of molecular motion. The object or substance is hot when the molecules   move   fast. The object is cold when molecules move slowly. In a piece of ice molecules are motion slowly they all more or less hang together. When the ice remains is solid. If the ice is heated it melts. Then molecules begin to move faster and they can no longer hang together to from a solid. And the ice convert to water. When the water is heated its boiled   and create vapor where all molecules move so faster and jump clear to liquid. When a cubic volume pressure increase that’s time heat increase. It has been seen that gaseous molecules are move so fast than other molecules.

Vacuum is the absence of air or other matter. If one travel far above the earth’s surface, hundreds of miles or more into space, it find no atmospheric at all. No air at the distance from the earth. In the air there find only few particles which is widely scared. It is called vacuum. How can one create Vacuum? For find a vacuum one need not to leave earth. One can produce vacuum anywhere from earth, one of the best example is a glass tube closed at one end with a dish of mercury which is contain a very heavy metal that is liquid at atmospheric temperature. This tube fully fill up by mercury and then closed tightly for producing a vacuum. Then turn the tube, leaving the upper part of the empty tube. Since no air can enter this upper part of the tube contains nothing.  That is it contains vacuum. It has been shown with a barometer in the schematic diagram. One can also do it with a normal temperature and atmospheric pressure.

The air has weight just has any other material object has weight. Generally it cannot think air has weight because it cannot see but one can feels it weight and movement for a certain period when air blows around us or human body. However since the air is an object which have weight. The air is pulled toward the earth by gravitational attraction.  At sea level and at as average temperature a cubic foot of air weights about 0.08 pounds it seems a very small weight. However the blanket of air the surrounds the earth is many miles thick. It means that there are in effect many thousands of cubic feet of air, piled one on top of another all adding their weight. The real weight of the air or its under ward force amounts is calculated about 15 pounds which is found in sea level. Generally fish are subjected to much greater pressure more than 100,000 psi at several thousand feet down in the ocean.

Gravity is the attractive force which has all objects toward each others. One of the best example is stone which is hand fall from the earth to ground. The earth attract or love  the stones and it is pulled toward the earth. Another best example is a car being driven up a hilly area where a hood part of the engine power is being used to overcome the gravity. And raise the car against the gravitational attraction. As like as when a car can cost down a hill with the engine off cause of the gravitational attraction of the earth on the car. It is measure gravitational attraction with terms of weight. It has been fixed a object such as a scale where its weight is 12 pounds. Its mean that the object has enough mass for the earth to register that much pull on it.  It is gravitational love  or the pull of the earth that give san object its weight.

What is the snap method of timing?   What are it’s advantage and disadvantage?                             Snap method of timing:                                                                        Snap method of timing is one the stop watch timing element at which no time is lost,more accurate time is obtained.                          Advantage: 1.        No time loss. 2.        More accurate elemental time is obtained. 3.        Help   the analyzer.                       Disadvantages: 1.        A series of subcontraction is essentially needed. 2.        Critical cost is high. Mathematical Problem: Element                                    Cycle Efficiency 1 2 3 4 1.        Position and hold brochure . 0.12 0.81 0.53 0.73 120 95 2.        Insert and put aside. 0.20 0.40 0.61 0.80        1. 0.94 1.16 1.36

a.        No slip at boundary. b.       Due to viscosity there is a shear between fluid layers which is given by Ʈ= µ du/dy for flow in X direction. c.        The flow is rotational. d.       Due to viscous shear, there is continuous dissipation of energy   and for maintaining the flow energy must be supplied by externally. e.        Loss of energy is proportional to first power of velocity and first power of viscosity. f.         No mixing between different fluid as long as pVl/ µ is less thsn critical value of Reynolds number.  Examples of Laminar or viscous flow: 1.       Underground flow. 2.       Flow past tiny bodies. 3.       Flow of oil in measuring instruments. 4.       Movement of blood in the arteries of a human body. 5.       Rise of water in plants through their roots.