Recent content by Fascheue

I think I understand why devices like diodes and transistors are non-linear. The voltage/current functions that those devices obey are non-linear functions. Resistors, capacitors and inductors obey linear functions. I’m struggling to understand what it means for a complex circuit to be linear...

But what do V and I refer to? I understand in the context of a component like a resistor that has a singular voltage and current. Most circuits don’t have a voltage/current, they have multiple nodes or segments with varying voltages and currents. I don’t understand how the concept of linearity...

Many circuit analysis techniques only apply to linear circuits. I don’t quite understand how to distinguish between linear and non-linear circuits. I understand the mathematical concept of linearity. I understand why components like resistors, capacitors and inductors are linear. I don’t quite...

A common equation for an electromagnetic wave is Ey = Eocos(kx - wt + phi). According to this equation, wouldn’t the intensity of the electric field extend indefinitely in the y-direction? How does this make sense?

Are there also two kinds of dot products then? One involving multiplication 1 and the other involving multiplication 2?

like this? ## \begin{equation*} \frac{\partial}{\partial x} * y = \frac{\partial y}{\partial x} \end{equation*} ? ## Couldn’t we then do this?## \begin{equation*} \frac{\partial(x^2)}{\partial x} * y = \frac{\partial }{\partial x} * x^2*y = \frac{\partial(x^2y)}{\partial x} \end{equation*}...

Divergence & curl are written as the dot/cross product of a gradient. If we take the dot product or cross product of a gradient, we have to multiply a function by a partial derivative operator. is multiplication by a partial derivative operator allowed? Or is this just an abuse of notation

I see. Is this only true for the gravitational force? Does the light cone modification work for the very similar Coulomb’s law equation?

In classical mechanics, the gravitational force is described by the equation: F = Gm1m2/r^2 What would this equation - or other similar equations - look like in special relativity? This equation cannot be correct because it implies that the force acts instantaneously.

Can you dumb down the four-vector stuff for me? Can you not solve these problems with F = dp/dt, where p is the standard 3-dimensional xyz momentum vector? The only familiarity I have with with - what I assume are - four vectors, is solving problems using spacetime intervals. They had a fourth...

Can special relativity handle acceleration? I believe the answer is yes, but I don’t recall dealing with any acceleration problems when I took SR. I remember using the time dilation, length contraction and Lorentz transformation equations. These equations all assume constant motion iirc.

The MOSFET in the triode region is being modeled as a resistor. From ohm’s law, the current across that resistor in the second image should be equal to V/R, where V is the drain-source voltage. In the equation I = Vds/R, there is no gate-source voltage dependency. And isn’t the second image...

I’ve attached two images from my textbook. One describing how MOSFEET’s act like small resistances when in the triode region and open circuits when in the cutoff region, the other a list of equations describing the behavior of an NMOS transistor. I’m having trouble making sense of these two...

L = T - U T = (1/2)Mx’ ^2 U = mgh If I plug these values into the Lagrange equation the right-hand side becomes ma and the left-hand side becomes 0.

I meant to write constant speed, not constant velocity. Also, I forgot to mention that I’ve already solved the problem with Newtonian mechanics. I’m struggling with the Lagrangian part of the problem. Wouldn’t the Lagrangian just be a constant in this case? If the speed is constant, T should be...