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Temperature compensation for level sensing technique
Dear Friends, I am trying a simple method to sense liquid level in an open tank using hydro-static principle. Though it resembles bubbler/purge method of level sensing, it avoids the need of external...
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(D'arsonval galvanometer) moving coil meter
Hello, just been reading a little bit about the basics of moving coil meter and one thing is bugging me. First if we have a basic square looped coil in and uniform magnetic field. There is torque ( m x...
View ArticleBoltzmann's entropy/ Microcanonical Entropy
Hey guys, i am reading something about entropy. :confused: And got a question. The boltzmann entropy is defined by: [itex] S=k\cdot \ln{W} [/itex] [itex]W[/itex] is the number of microstates connected...
View Articlehow can diffraction be explanined using the concept of wavelength.
hi.. I have been struggling, since a long time, to understand how is the diffraction pattern obtained by a slit of width of the order of the wavelength of light used is obtained, but found no answers!...
View ArticleHow does heat affect bonds and their motion?
If I had a some covalent molecules with a total intermolecular bond strength of 100J and total covalent bond strength of 100J and when I supply 100J of heat into those molecules, how are the bonds...
View ArticleDiode and doping on N and P regions
Dear forum, in a diode semiconductor, the N region is rich in electrons. The P region is rich in holes. Is the number of extra electrons in the N region equal, larger or smaller than the number of...
View ArticlePotential energy of pendulum in terms of displacement.
Hi guys, I'm having troubles finding how to write the potential energy of a 1D pendulum down. In terms of displacement however. This should be easy and it is, but my professor had this nice "clean"...
View ArticleIR thermometer pointed up into a cloudy sky?
A physics stack question asks why when the air is hotter then your body thermodynamics allows your body to operate as a heat engine as a heat engine must have a sink for waste heat. See question here,...
View ArticleRectangular Waveguide centered at the origin
Hello, If a rectangular waveguide (or square well, etc) is centered at x=a/2, y=b/2, solution (e.g. for TE mode) is: H = Ho Cos(m*pi*x/a) * Cos(n*pi*y/b) (n,m = 0,1,2,...) So for TEn=0,m=1, H = Ho...
View ArticleAcceleration right after ball bounces
Suppose a ball falls from a very high altitude to the ground and bounces in form of a completely elastic collision. What then is the acceleration on the ball immediately after the bounce? It is...
View ArticleAn anomaly in high-impedance inductors ...
Hello, first post here, my passion is electric motors, wind turbines, etc ... yes i am very boring ! I've been testing coils for my motor design for a couple of years now. I've written my own software...
View ArticleFerroFluid Experiment in Lab
Hi there; Right now I am currently in both a second level introductory college level Chemistry and Physics course. In chemistry, we have a semester project to do, and with a little physics background,...
View ArticleEarths magnetic field
Does the Earth's magnetic field rotate with the Earth? I am figuring it's stationary as a magnet that rotates through it's pole to pole axis does not exhibit a rotating magnetic field so why should the...
View Articleproperties of an electromagnet
We are going over magnetism in my Physics 2 course but we barely covered electromagnets. I was wondering what the math equation for field strength would be for an electromagnet. In other words, how is...
View ArticleKirchoff's Rules
Hello, I am having difficulty when trying to solve problems requiring kirchoff's rules. The problem I seem to be having is following the convention used by my book. I can't tell when the current is...
View ArticleHow fast does hot air rise?
So for a class I am designing a solar dehydrator and I want to know how fast the hot air will rise out of the dehydrator. For calculation purposes assume the hot air is 120°F @ 30% relative humidity...
View ArticleSurface field vs pull force(attraction force) of multiple magnets?
In the following "semi" table, is a group of magnets, all seem to have the same Surface field but all different pull force(attraction/repulsive force at maximum with gap = 0). How is it possibile to...
View ArticleForce of a nail inside an MRI machine
I just want to gain a ballpark estimate for how much force an MRI machine can generate on a small object such as a nail.. lets say the magnet is 1-2 Tesla. Very rough estimates are ok.
View ArticleBoit's experiment on electrostatics
Hello. On the web address http://etc.usf.edu/clipart/35600/35631/boit_35631.htm there is an apparatus allegedly used by a scientist named Boit. However, I can find no reference elsewhere on the web...
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