Inmarsat analysis for missing flight MH370
Initially the pings from Malaysian airlines flight MH370 could only determine the distance of the aircraft from the satelite based on round trip times of the pings sent at one hour intervals. Taking...
View ArticleCentrifugal force? Why does the Earth bulge at the equator?
I'm trying to understand why a superdeformed nucleus may be represented as bulging perpendicular to the axis of rotation, and I'm guessing this is akin to why the Earth does so too. I've gone through...
View ArticleDerive an equation
I need some help with an equation. I will use to find the value of acceleration due to gravity. With a air track and a spring attached to a glider we should find the value of "g". The track is inclined...
View ArticleScrew theory and Chasles' theorem
I am currently working on my masters and happened to stumble upon screw theory, of which I have no previous experience with. Fundemental to screw theory is Chasles' theorem or Mozzi's theorem that...
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A Figure in Griffith's Intro to Electrodynamics
I am really loving this book. But I have come across a figure whose purpose I just don't understand. It is shown when Griffiths is introducing the concept of self-inductance. He talks about how a...
View ArticleParition function for Boson "gas" with two quantum numbers
Let's say that we have a system of non-interacting Bosons with single-particle energies given by, [itex] \epsilon_{p,m} = \frac{p^2}{2m} + \alpha m [/itex] where [itex] m = -j, ... ,j [/itex] and we...
View ArticleMotion in a rapid oscillating field
Hello, I've been making my way through Landau-Lifshitz's "Mechanics" book, and I've come across a bit of math I'm not too sure about. What I'm confused about is here:...
View ArticleGibbs Free Energy A Measure of Stability
Hello everyone, I am having a little difficulty understand precisely what Gibbs free energy is. I have read in my textbook that a negative change in Gibbs free energy implies that the substance under...
View ArticleSpectral Reflectance Curve
Hello, Are spectral reflectance curves dependent on the interface between the reflector and surrounding medium? For example would they be different if I had a silver mirror in air compared with silver...
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Finding Total Electric Field
Hi I am pretty confused on how my book is doing the calculus of electric fields. Basically I don't understand how their equation makes any sense (The integral equations on the second page). How does...
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Bar suspended by rope kinetic energy
If I needed to calculate the kinetic energy of a bar suspended by a rope at one of its ends, in other words, a bar pendulum, do I need to calculate the kinetic energy of the center of mass plus the...
View ArticleHomeopathy and the second law of thermodynamics
Homeopaths assert that dilution of a medicinal substance in a water -alcohol mixture, followed by forceful shaking (called "succussion") would create a memory of that substance in the solution. Critics...
View ArticleVolume charge density w/o surface charge density
Im confused by a concept i have run across in Griffiths electrodynamics. [itex] E_{out} - E_{in} = \frac{\sigma_{free}}{\epsilon_0}[/itex] However, in the case of a uniform, circular charge density,...
View ArticleElectric potential halfway between two equal but opposite charges
I'm having a hard time understanding why the electric potential halfway between two equal but opposite charges is 0. If I put a positive charge halfway between a 5 mC charge and a -5 mC charge, it will...
View ArticleHow to write coupled mode equation of a given structure
Recently I am reading the papers in the field of PT symmetry systems. What I am confused is that in these papers, authors directly write out the equations describe the dynamics of the given systems(...
View ArticleAnalogy between satelite orbit and mass oscillating through earth
The period of a satellite revolving around the earth earth at surface height is equal to the period of any mass thrown through a hole of the earth(which gains a simple harmonic motion)... It seemed...
View ArticleRelation between Impulse and Conservation of Momentum
First post here. This question has two parts. (1) Connecting the dots between the Impulse-Momentum Theorem and the Law of Conservation of Momentum and (2) Book recommendations for a more theoretical...
View ArticleFlow Past Sphere at High Re - Velocity Behavior
Hello, I'm currently working on simulations in Solidworks of the flow of air (v = 450 m/s) around a sphere (radius = 1.5 cm). The results have been used in a cut plot representing the velocity in the x...
View ArticleVector in orbital theory.
Hi, I need help with the following equations. n = r/r (unit vector in r direction) v =d r/dt = dr/dt n + r dn/dt L = r X (mv) = mr^2 [n X (dn/dt)] how did this mr^2 [n X (dn/dt)] came about? I would...
View ArticleTOTAL FLUX through a solenoid
suppose a solenoid has N turns What is the Flux through the Solenoid? similarly if a coil has N turns , what is the flux through the whole coil? i know how to find flux through a given AREA,,,like a...
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