Recent content by Joseph M. Zias

I think we can close this thread. I found the enthalpy of H2O l is different that the enthalpy of H2Og so apparently the PV work is included when a gas is involved.

Do the published values of Enthalpy include the work done against a constant pressure, e.g., the atmosphere? (I am not a chemist). I am reviewing enthalpy and entropy as part of the statistical mechanics applied to transistors. I assume, from my reading, that the work done would mostly apply...

Revisiting a feedback loop circuit of decades ago. I have two uA709s and 3 more on the way (Ebay). But I thought I would check to see if any "new" op amps have the same feature. Being able to tailor the response allows for some interesting experiments, for example, inserting a right half...

Does anyone know of a modern op-amp (available) with a frequency compensation input as the very old 709 had?

Dave, A very good reply. I attended one of Middlebrook/Cuk seminars in 1984 and bought his DVD years later from his group Ardem.

Some of the great Analog Engineers and Teachers have passed; Bob Pease, Jim Williams, R. David Middlebrook. I would like to inform/remind engineers and students interested in Analog Design of Dr. R.David Middlebrooks work. He was a prolific author and many of his papers are available through...

It seems that in the case of Velocity vs time we can draw the graph and calculate distance or acceleration but are we then also saying that is not permissible to draw a vector since the magnitude is is undefined or not permitted? My similar question in the EE group regarding the S plane seems...

Well, very good comments and I think takes care of the S plane. Comments on the physics site are interesting.

Please explain.

Good point that radians are essentially dimensionless. In this case we have a magnitude of sec^-1 and then divide it up appropriately; as you note the real part gets nepers per second and the imaginary part gets radians per second. However, we could have also used frequency for the vertical...

It seems we can use magnitude for a V vs t vector. Suppose we have V=5m/s and t=5s. We then have M=square root 50. Now if we start with M=square root 50, angle 45, and disassemble it to an x and y component we would, of course, have t=5 seconds and y=5 m/s. We have just spread out the square...

This post parallels a post I made in electrical engineering regarding the S plane. I thought I would post an equivalent in basic physics. So, given a graph of velocity vs time we have on the vertical axis meters/sec and the hormonal axis just meters. Given a plot of V vs t we know the area...

Well, I see the logic as I noted earlier. However, the dimensions of the y axis are radians/sec. How are we ignoring that in the quantity "square root (a^2+w^2).

Thank you for the detailed response. That looks to be more work than I am ready to attempt. I did find for <$300 a 7000 series rack mount scope that does the job. I am using the vertical signal output to measure feedback loop gains in the fashion of HP/Middlebrook.

In the S plane we have a real component, usually called sigma, and the imaginary component, jw, in radians/sec. The real component is sometimes called nepers per second, with nepers being dimensionless. However, if we draw a vector in the s-plane, say s - s1, in polar form, what are the units...