How and What

 Theory of relativity and interrelation between space time and mass in space-time continuum  Many of us know space and time to be different entities, but it is not our fault as we are only exposed to classical mechanics in our daily life. In classical mechanics, Euclidean space is used, instead of space-time. In classical mechanics, time is considered to be universal and constant being independent of all possible variables. This is true if the observer and the event are in the same frame and all these things are happening on the surface of earth. In contexts related to relative theory, value of time varies according to the velocity of the observer or mass of the body to which time is associated. In space-time concept, time is considered to be the fourth dimension. If we have to define a point in the space then we need three common dimensions which are horizontal, vertical and depth (x, y, and z) and another imaginary dimension time. If there is no ma...

Effect of speed on time and special theory of relativity  According to Albert Einstein’s special theory of relativity, the time interval between two respective events is different if measured from different inertial frames. For Example, if an observer moving with some velocity sees two consecutive events in a stationary platform and if he measures the time interval between the events then he will find that the time interval observed by him is larger than the time interval observed by an observer stationary with respect to the platform. Let’s illustrate this phenomenon with a hypothetical experiment to understand it better. Consider that two mirrors are fixed horizontally, facing each other. Let the distance between the mirrors be‘d’, name the top mirror as M1 and lower mirror be M2. Consider an observer ‘o’ standing at a distance as shown in Fig 1. If a light pulse is reflected back and forth by the mirrors. Let the first reflection at M1 be ‘event 1’ and the se...

Injection Moulding steps and important parts of a mould An injection mould   is a machine that converts molten plastic to  desired shapes of high accuracy which are difficult to form by conventional machining operations. This process is used to produce almost every plastic component used in our daily lives. Some small metal components are also manufactured with this process if high level of accuracy is required for mass production. The surface finish of the components made by injection moulding is also very good and products are almost ready to use i.e no further polishing or machining is required, though tumbling is done to remove the marks of ejector pins and runner gates and lines left by joined parts.  Components produced by injection moulding posses high mechanical strength due to better molecular interlocking in the material of the component. When the molten material is injected in the cavity with high pressure then molecules of the component being for...