Recent content by darkfeffy

Hi Willem2 Thanks for your reply but I have to disagree with you because, as you can see in the datasheet that I originally attached, it is possible to have a pulse power in the tens of kilo watts (yes, it says 10,000W) as long as the pulse duration is shorter than 1 micro second. Apart from...

Thanks for the reply, Don. I guess I should re-phrase my question by asking: Assuming the datasheet resistance value stays roughly constant, then of what importance is the wattage rating if one cannot even attain that without risk of arcing? Shouldn't the datasheet wattage be taken from V^2/R...

I suspect this limit represents the strength of the dielectric. If so, then how can the resistor's rated power ever be attained/achieved? Of what use is that figure then?

Hello there, I am wondering why the resistor maximum voltage is not simply the square root of the product of its wattage and its resistance. According to the attached datasheet (pdf) for example, the maximum voltage of a 2.2 mega ohm, 0.25W resistor, is 250V (instead of 742V as calculated)...

Thanks for the tip.

Hi Could anyone give me a hint on getting a closed form for the following integral: \int\frac{1}{k + sin(x)}dx where k is a constant. Thanks. e.

Hi Jtbell, Thanks for your response. I was reading a book on linear induction motors, and therein it was written: \frac{de}{dx}=\frac{db}{dt} + v\frac{db}{dx} The first term is referred to as a transformer voltage, and the second, a speed voltage. I want to know how to get this from...

Hi, In classical induction machine analysis, the induced voltage (or curl of the electric field) is equal to the time rate of change of the magnetic field (B) plus the 'speed voltage'. This is understood very easily from electrical circuit models of the machine. However, going purely from...

Explanation of '3f' By '3f', I mean '3 multiplied by f'. In other words 150Hz. If a 150Hz sinusoidal signal is rectified (i.e. absolute value of sin(3wt)), then it will look like the red signal in my first attachment. Sorry for this confusion.

Hi, I wish to obtain the Fourier series of the signal in red (please see attached figure fig1_sine_plots.png). Basically, it is a full-wave rectified 3f sinusoid, where f = 50Hz. The blue signal represents a sinusoid with frequency f = 50Hz. In the following equations (please see attached...

Hi everyone, I know this should be obvious, but there's something I am just NOT getting. Imagine a simple series RC circuit with a DC source as shown in the attachment. As can be seen from the picture, I have solved the differential equation in capacitor current in the time domain. In...

Hi guys, I know this should be obvious, but there's something I am just NOT getting. Imagine a simple series RC circuit with a DC source as shown in the attachment. As can be seen from the picture, I have solved the differential equation in capacitor current in the time domain. In order to...

Thanks DH for your brilliant reply which really doesn't add much information :-)

Thanks Dick.

Thinking it might just be an assumption that this last term is exceedingly small compared to the first.