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RPM(speed) of electric motors

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There are so many quantities which are responsible for the speed of motors, So let's start with few of them: We know Synchronous speed  Ns =120f/P & S = (Ns-N)/Ns From where N = Ns - SNs i.e. N = Ns(1-S) & Hence Speed of rotor is N = (1-S)120f/P Where, N = speed of rotor f = frequency of supply voltage S = slip of motor & P = no. of poles on stator From this formula we can see that speed is depends upon frequency of supply voltage, slip of motor, poles on stator, etc. Other then these Speed also depends upon supply voltage & also on loads. .. .. .. While, In DC motors We know E = ZNP phi/60A Now N = 60AE/ZP phi Where N= speed & it depends upon the following quantities: A = no.of parallel ways Z = no.of conductors P = no. Of poles Phi = flux cutting the conductors etc. .. Please feel free to give suggestions if there is any error. .. Please support if you like this:                     SOCIAL HANDLES Website: curi...
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Magnetism

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Magnetism

Electric fields and magnetic fields might seem different, but actually, they're part of one larger force called the electromagnetic force. Charges that aren't moving produce electric fields. But when those charges do the motion, they also create magnetic fields.

Let us take an example while explaining this concept: 

when supply is given in the electrical machines, different types & kinds of magnetic fields are formed in different-different electrical machines (motors, generators, transformers, alternators, etc.). These magnetic fields are created by the flow of charges (electrons) when they are pushed by the supply voltage.


So whenever there is a moving charge (or current flowing) there will also be a magnetic field.


For example, a magnet is only a magnet because of moving charges inside it.

 And hence charges moving in a current carrying electric wire also produce magnetic fields.

This is the main & basic concept behind the working of electrical machines.

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Why earth terminal of 3-pin plug is long & thick as compared to phase & neutral?

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There are very important reasons for it. In this article, we describe it deeply. So let start. First, why this is longer than others? So the answer is this is made longer because it should be connected first while connecting the plug to a socket other than phase & neutral & Also should be removed at last after the removal of phase & neutral. Since, if there is any leakage current then this should be earthen first to ensure safety to the living body. As this current will goes to earth with the help of this earthing terminal & not through the human body. Now our second why this is thicker? Well, there are 2 most important reasons behind it. The first is quite simple that this earthing terminal should not be connected to phase & neutral of the socket. Because earthing has nearly up to 8-ohm resistance if this terminal is so connected to them all voltage will become zero, to prevent this terminal is made thicker & hence cannot be connected to phase & neutral ter...
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Difference between MCB & ELCB

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M.C.B. V/S E.L.C.B. First talking about their full form so M.C.B. == Miniature Circuit Breaker E.L.C.B. = Earth Leakage Circuit Breaker MCB protects against short circuit faults & overload conditions. In these situations, MCB starts operation by tripping off the circuit & hence protect against further more dangerous faults or accidents. MCB is mostly used in domestic purposes & in auxiliary supplies. While ELCB operates when there is a flow of current starts into Earth through phases by any other fault or through the body of the machine. Such as, When MCB or any other protection such as fuse is not connected in the circuit & if there is any short circuit or overloading fault created then higher current (than the ratings of the conductor) flow through them which may cause to break the insulation of the conductors & the conductor may join to the earthing wire. In these conditions, ELCB operates to disconnect the circuit & hence protect against major accidents. Now...
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