1. How does the Induction motor work? (OR) Why does the Rotor rotate? When the 3 phase stator windings are fed by 3 phase supply, a magnetic flux of constant magnitude which is rotating at synchronous speed is set up. The flux passes through the air-gap and sweeps past the rotor surface thus it cuts the rotor conductors. Due to the relative speed between the rotating flux and the stationary rotor conductors, an emf is induced in the stationary rotor conductors as per the Faraday's laws of electromagnetic induction. The frequency of the induced emf is the same as the supply frequency. Its magnitude is proportional to the relative velocity between the flux and the conductors. Its direction will be as per Fleming's right hand rule. Since the rotor conductors form a closed circuit the rotor current is produced. This current's direction will oppose the very cause producing it ( as per Len's law) Here the cause is the relative velocity between the rotating flux of the stator...
1. Explain The Concept Of Density ? One of the properties characteristic of every material is its density. We observe that a small piece of one material may be heavier than a much large piece of another material. The mass per unit volume of a substance is called its density p = m/V Units of density are determined by dividing the chosen unit of mass by the unit of volume, as kilogram per cubic meter, gram per cubic centimeter, or slug per cubic foot. It is sometimes helpful to use another quantity called weight-density, or weight per unit volume: D = W/V Since W = mg, we have a simple relation between density and weight-density: D = ?g Weight-density is commonly used when we are concerned with effects depending upon force, while density is used when mass is to be considered. Solids and liquids are only slightly compresses by even large stresses; hence their densities are...
Here are top 200 Structural Analysis Interview questions and answers are given just below to them. These sample Structural Analysis questions are framed by experts. who train for Learn Structural Analysis Online to give you an idea of Structural Analysis questions which may be asked in interview. We have taken full care to give correct answers for all the questions. Do comment your thoughts. Happy Job Hunting! 1. What is meant by Finite element method? Finite element method (FEM)is a numerical technique for solving boundary value problems in which a large domain is divided into smaller pieces or elements. The solution is determined by asuuming certain ploynomials. The small pieces are called finite element and the polynomials are called shape functions. 2. List out the advantages of FEM. Since the properties of each element are evaluated separately differnt material properties can be incorporated for each element. There is no r...
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