Recent content by GeorgeRaetz

You may want to sharpen that as: "Poynting vector is the amount of energy flowing at the point of its evaluation per unit time and per unit of cross sectional area transverse to its direction."

The fundamental problem here is that after you write up and solve the equations of motion for the charges, you will find the charges accelerating. The conventional particle-field description predicts loss of particle energy & momentum through radiation. So the equations of motion would seem to...

Here is a hint: http://en.wikipedia.org/wiki/Chemical_potential#The_values_of_the_chemical_potential

Interesting how the science changes. When I was in grade school, prevailing theory was that oil did originate from dead dinosaurs; a dinosaur still serves as the trademark of a well known oil company. Current theory is that micro-organisms are the source of oil. And then there is notion of...

Might try this: After time t, Probability for one event in process1 to occur over interval dt and N events in process 2 occurring after time t has elapsed should be the product: λ1 exp(-λ1 t) exp(-λ2 t) (λ2 t)N/N! dt Integrate over all positive t to get answer to question 1.

For static fields, Electric field is the (negative )gradient of potential. (regardless of charge configuration) When you say E=V/d you are approximating the gradient with a difference quotient and that would be the major error source I would think.(assuming there are no spurious electrochemical...

For fun we can calculate some pressures. For the capacitor in the TV, assume 1 millifard at 300Volts. Guess a can size of 2" diameter by 3" long. then the pressure calculates to (1/2).001 F (300 Volt)2 /(pi (1 in)2 3in)~3 atm. For the super Cap mentioned assuming a mass density of 2 gm/cc we...

318 watt-hr/kg ~1.1 106 J/kg. Energy density of ordinary gasoline is roughly 3 107 J/kg. So they have a way to go to even match the energy density of good old fashion gasoline. The exploding capacitor you mentioned most likely had burst from excess fluid pressure caused by overheating--not...

OP (Terp) is asking to convert from failures per year to probability that failure will occcur in one year. That can only be answered with knowledge of statistical distribution of failures over time. However, if detailed statistical data is not available, one resorts to a statistical model. I...

This is classic Poisson process. The probability of the valve lasting a time t with NO failure is: P0(t)=exp(-lambda * t) Here, The rate constant lambda=15/106 hr =.13 yr-1. Example:The probability of the valve lasting one year is exp(-1yr*.13/yr)~.88

Theory is based on assumption that any nucleus decays independently of the others at a random time. That leads to Poisson statistics which provides results such as exponential decay with the half-life rule. All of which can be checked with experiment.

Maybe a numerical example will clarify: Start with 4 moles of gas A occupying 4 liters in one corner, and 12 moles of gas gas B occupying the remaining 12 liters of the containter. The temperature is held at constant T=195K, that makes the pressure of each portion about 16 atmosphere. Let A...

Experiments with vacuum Rabi oscillation http://en.wikipedia.org/wiki/Vacuum_Rabi_oscillation suggests that spontaneous emission is reversible, but that goes off topic. Need a new thread for that in a different sub-forum. Penrose argues as follows: reverse exactly the velocity of every...

Perhaps I didn't explain it clearly. Motion is unbounded, so particles end up at infinity. Here's another example. Box with a partition has vacuum in one half, air in the other half. Remove the partition and density equalizes. But wait long enough (Poincare recurrence time)and the system will...

Classical thermodynamics starts with a system of many variables--the positions and momimtua of each molecule in a gas for example; that's called the microstate. From the microstate a contracted description in terms of far fewer variables is calculated that's called the macrostate. The macrostate...