why when we perform SCC of an alternator we always get a
straight line even when 125% rated current is flown?
Answer / moody
nice question
we got astraight line becas when we make ashort circuit on
the armature winding so only alittle net mmf is produced
from the field and armature reaction so the field current
used not exceeding 20 % of the field current for rated
voltage and in the drawing os o.c.c this region is
astraight " non saturation"
draw the phasor diagram and u will see the answer by ur self
| Is This Answer Correct ? | 7 Yes | 4 No |
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Question 100 - (a) Time evolution in Heisenberg picture, according to Ehrenfest theorem is m (d / dt) < r > = < p >, where m = mass, r = position, p = momentum of a particle. If v = velocity, prove that m < v > = < p >. (b) Lande g-factor is given by Gj = Gl [ J (J + 1) - S (S + 1) + L (L + 1) ] / [ 2J (J + 1) ] + Gs [ J (J + 1) + S (S + 1) - L (L + 1) ] / [ 2J (J + 1) ]. If Gl = 1 and under approximation of Gs = 2, prove by calculation that Gj = (3/2) + [ S (S + 1) - L (L + 1) ] / [ 2J (J + 1) ].
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ELECTRICAL TECHNOLOGY - EXAMPLE 16.1 : According to Shockley equation, the I - V characteristic of a diode is approximated by I = IS [ exp (nVD / VT) - 1 ]. For silicon, let the reverse bias saturation current IS as 0.000000000001. If n is ideality factor with value of 1.5, VT as thermal voltage drop of 0.026 V at room temperature, what is the value of current I that passes through the silicon diode in the heater of evaporator when the forward voltage drop VD = 0.026 V? Please take note that exp is the exponential function with e(1) = 2.718, e(2) = 7.389.
Who built the first production scale pla (polylactic acid) facility?
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