Recent content by The_Lobster

I'm reading about constant-charge capacitor microphones, and they are essentially made up of a parallel-plate capacitor (one plate fixed, the other moving to sound pressure), in a circuit with a series resistor and DC source to provide polarising voltage. The circuit is basically an RC...

AlephZero: Are you saying that that equation is pretty much: v = - A\omega \sin \omega t ? Does that mean I can consider the "maximum particle displacement" in the first equation, as the amplitude, A?

Thanks, AlephZero! Typical of me getting thrown off by poor notation...

I'm reading a book on microphones and came across the following: and then it goes off talking about something else... I feel stupid for asking this, but I don't get how the above equation works? For one, I thought cross products could only be be involving vectors? Aren't all the terms...

There's only one thing I still don't get: If the impedance is at its lowest at resonance frequency, why doesn't the voltage go down as the current goes up? Effectively negating the effect? Since there is less impedance in the circuit? This way it seems as if the power should stay the same... I...

Thank you so much, sophiecentaur! That makes all the sense in the world! I learned something tonight :)

I'm considering any circuit I think, but would that have any effect (I assume it will since you asked! :) ) I'm basically wondering if, in an a.c. circuit, a measured resistance of a resistor could be affected by temperature increasing in the resistor due to higher frequency, or at resonance...

Homework Statement Do you think a meter will handle an a.c. current of any frequency? Homework Equations The Attempt at a Solution Since we can illustrate an ammeter as a moving coil with a resistor in parallel, and since all elements in a circuit will exhibit inductive and...

In an L-R-C circuit, if the reactance of the capacitor equals that of the inductor, X_L = X_C, and consequently the current is at it's max and we have resonance, will the temperature in a resistor with a positive temperature coefficient increase faster in this situation, and thus get increasing...

Homework Statement If possible, find reasons why the resistance of a resistor may have a different value when measured with a sine wave signal (a.c.) than when measured with a d.c. (dirrect current) source. Homework Equations The Attempt at a Solution Please correct me if anything...

Sorry if this is a no-brainer, but I just can't seem to find much info about this.. All sources only talk about a single wave, most often a sinusoidal wave, and never mentions how the situation is like when there is a complicated sound signal with lots of stuff going on (different timbres for...

How does exactly higher capacitance have "more bang for your buck"? Hi! I'm trying to really grasp the concept of capacitance. Whenever I see a description of the definition, C=Q/V, they always say either: "More charge stored per potential", or "more bang for your buck". I don't really...

Thank you! But what about the contribution from the voltage source once we put that back?

Homework Statement Find the voltage v across the 5 Ohm resistor as shown in the attached drawing. Homework Equations Ohm's law, V=IR The Attempt at a Solution I have done plenty of these using different techniques, superposition/source transformation, nodal or mesh analysis, etc...

There's a problem in my book where it asks me to find the Thevenin and Norton equivalent circuit of the attached circuit, as viewed from AB. I believe I know the answer, but just had to check to be sure this is not a trick question? Isn't the Thevenin eq. circuit as seen from AB exactly the...