6 differences in electrical engineering principles in theory from practice?

Q2: A Cockcroft-Walton type voltage multiplier has ten stages with capacitances, all equal to 1.5 µF. The supply transformer secondary voltage is 800 kV at a frequency of 50 Hz. If the load current to be supplied is 8 mA, find (a) the percentage ripple, (b) the regulation, and (c) the optimum number of stages for minimum regulation or voltage drop.

Q4) A 230/460-V transformer has a primary resistance of 0.2 2 and reactance of 0.8 and the corresponding values for the secondary are 0.6 ≤ and 1.6 ₪ respectively. Q4.1) The transformation ratio of the transformer = Q4.2) The total resistance and reactance of the transformer referred to secondary side ohms and ohms respectively. Q4.3) The voltage drop in the transformer referred to secondary = Volts Q4.4) The secondary terminal voltage when supplying 12A at 0.8 p.f. lagging = decimal places) Volts

4. Which of the following is a mathematically incorrect operation and why? a) gradient of a divergence b) curl of a gradient c) gradient of a curl d) divergence of a curl

Jm = 1 kgm^2 Dm = 5 Nms/rad Please solve with steps

What is the difference between performance and potential?

12. You plot the current-voltage characteristics of a new non-ohmic device, perform a curve fit, and discover the current as a function of voltage is given by the equation: I = (9Amp/volt")V² – (7Amp/volt) V (a). Perform calculations to find the slope of a line tangent to this curve when V = 4.15 volts. (b). Calculate the effective resistance of this device when V = 4.15 volts. This device is Non-Ohmic!