A bank of three identical unity ratio transformers is connected as shown in figure. At no load, the readings on ammeter A1 and A2 are 0.75 A and 0.46 A respectively.
If the transformer is connected in Star/Star with four wire supply, calculate the current in the line and in the neutral wire.
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In the circuit shown below, VBE= 0.7 V, the operating voltage VCE is?
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A3 Phase 275 kv transmission line has A = D = 0.85 < 5° and B = 200 < 75° Ohms. A load of 150 mΩ has to be supplied at UPF with same voltage profile. What is the reactive power support needed at receiving end?
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A 20 kW, 3 phase, 400 V, 4 pole, 50 Hz squirrel cage induction motor when working at rated voltage and frequency develops a full load torque at 1470 rpm. If the motor is fed from 40 Hz source,with its voltage adjusted to give the same air gap flux as at 50 Hz, the speed at which the motor would now run so that same full load torque, as at 50 Hz, is developed in rpm is ________.
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A short circuit test, when performed on HV side of a 10 kVA,2000/400 V, single phase transformer gave the following data 60 V, 4 A, 100 watts. If the LV side is delivering full load current at 0.8 PF lag at 400 V, the voltage to be applied on HV side (in volt) is ________.
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The matrix
is the augmented matrix of a system of linear equations. The arbitrary constants are needed for the solution of this system of equations are _________.
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If \(\begin{bmatrix} 0\: 1 & \\ -2\: 0 & \end{bmatrix}\begin{bmatrix} q\: -7 & \\ p\: 0 & \end{bmatrix}=\begin{bmatrix} 1\: 2 & \\ 0\: -1 & \end{bmatrix}+h\begin{bmatrix} 0\: -2 & \\ 6\: 3r & \end{bmatrix}\), then the value of p, q and r is
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The function f(x, y) =x2+ y2+ 2⁄x+2⁄y has
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A player tosses 6 coins, then the probability that both the faces have the same number is _________.
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P(number of heads = number of tails)
\(=\frac{^{6}C_{3}}{2^{6}}=0.1325\)
The particular integral of (D– 1)2y= xex is
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