Recent content by debwaldy

Would it be possible to just say that P = S and hence the voltage at the customer end will also be 33kV?

we have been told to assume that all voltage values given are rms voltage values so we don't need to worry about that...

Homework Statement A 33 kV single phase generator is supplying a customer a load through a cable with an impedance j2 ohms a.What voltage would the customer experience if rated current of 500 A is drawn at power factor of unity at the customer end? b. How much active and reactive power...

If i do this and substitute in t = 2 billion years i get a ratio of 0.1947, although I don't think that this is correct?

As in the equation N(t) equations? will the No be different in each case?

Homework Statement The present day value of the uranium isotopic ratio U-235/U-238 is 0.00723. The half life of U-238 is 4.51 x 10^9 and the half life of U-235 is 7.13 x 10^8 years. What was the U-235/U-238 isotopic ratio 2 billion years ago when the Oklo natural reactor was active...

1. Hi, I am trying to model the magnetic force between two cylindrical identical sized permanent magnets. I am using the Charge/Coulombian model to do this. This assumes that all of the "magnetic charge" is on the pole ends of the magnet, i.e. the flat surfaces at the top and bottom of each...

Homework Statement Hi all! I'm trying to solve the following problem but I'm not too sure of a few things. Write Matlab instructions to plot a three dimensional Gaussian: A = A0exp((x^2 + y^2 + z^2)/w^2) choosing appropriate values for A0,w and range of coordinates. Homework...

Homework Statement Hi, this question is really confusing me and preventing me from completing the rest of the question. It is probably a very simple problem but i just don't understand so any help would be much appreciated. A metal- filament lamp,rated at 750W, 100V, is to be connected in...

Homework Statement Hi, so I am just starting an rms voltage question but I'm a small bit confused. The problem states: A transformer having 90 turns on the primary and 2250 turns on the secondary is connected to a 120V, 60Hz source. Calculate a) the rms voltage and b) the peak voltage at the...

and i just use the current value i have already calculated? ok i think i follow now,thanks for the help

i don't understand,how do you solve that equation when you dontknow what V is, do i take 1.51V as the value for V in that equation?

Homework Statement Hi I've tried to solve this question but I keep getting stuck at a certain point, it probably very simple but any tips would be greatly appreciated The EMF of a cell is measured using a potentiometer and is found to be 1.51V. When a voltmeter, which has a resistance of...

Homework Statement A parallel plate capacitor is constructed by placing square metal sheets of side length 30 cm on either side of a sheet of polythene which is 2mm thick If the permeability of the polythene is 2.2 *10^-11 F m^-1, what is the capacitance of the system (ii)If a 50V power...

oh i think i understand now thanks a million,looked in loads of books but none explained it in the simple straightforward manner that you did cheers debs:-p