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...
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 terminal of the socket.
To understand Second we should know the formula
R = rho * length / area
Where,
R = resistance of the conductor
Rho = resistivity of the material of the conductor
l = length of conductor
&. A = cross-sectional area of conductor
& Here we consider conductor is an earthing terminal of the plug & socket
Now as in the formula if we increase the cross-sectional area of the terminal (A) {i.e. thicker the terminal}
The resistance becomes decreased.
& Hence leakage current can flow through it more efficiently to the earth.
Besides these, there are more advantages such as.
While fault condition when leakage current flow through earthing terminals P= I²R power loss also occurs this will create some few amounts of heat if the resistance of the terminal is more the more power will lose & more resistant will add in the path of this leakage current & may cause some shock to the living person.
This help me lot
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