Question re: Newton's 3rd law
I'm looking for knowledgeable help to resolve an argument between myself and someone else. A bowling ball is positioned, say one hundred thousand miles from the Earth, motionless, relative to the...
View ArticleUnderstanding Poynting's Theorem intuitively
understand that, broadly speaking, Poynting's theorem is a statement of conservation of energy. There are many forms of the theorem, so I will simply give my current intuitive understanding of it in...
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Electric field in all regions of cylinder
A uniform linear charge of λ is located along the z axis, and concentric circular cylinder of radius 2 [m] has a surface distribution charge of α . both distributions are infinite, the distribution of...
View ArticleLots of questions about optics...
Hi, I am new here and I've got lots of questions about optics physics. I hope everybody can help me out. First, please check my understanding of diffuse reflection:...
View Articleexample about tangential and normal unit vectors
Here is a example 1.3 from analytical dynamics of Haim Baruh. a particle moves on a path on the xy plane defined by the curve y=3*x^2 , where x varies with the relation x= sin(a). find the radius of...
View ArticleElectrical grounding and alternating current
When households are said to be grounded using an earth wire, electrons are supposed to flow to the ground because the ground is at zero volts. For example, if your the live wire touches the metal...
View ArticleNegative ions, static charge
In a famous experiment with a balloon and wool. http://phet.colorado.edu/sims/html/b...ricity_en.html Initially the balloon and wool pullover have no ions. I understand how positive ions are formed,...
View ArticleThermodynamic Rankine cycle
hi guys , I am studying thermodynamic cycles in my thermodynamic course , I have a question about the power cycles like Rankine , in these systems v use superheated steam to produce work from turbine,...
View ArticleYoung's modulus and temperature
Hi, I'm doing an IB extended essay in physics (like a 4000 word investigation) and I'm looking to do it on Young's modulus- in particular perhaps how temperature effects it. Is this legit? Like does...
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Center of gravity of a portion of cylinder
AttachmentsFigure # 1 Figure # 2 reproduced from http://www.lmnoeng.com/Volume/InclinedCyl.htmhttp://www.lmnoeng.com/Volume/InclinedCyl.htm Description The blue is the mass inside a cylinder. In steady...
View Articleheating up a wire with current
I have a question about an object heating up when electricity is applied. When putting electricity (say 10 to 15 A) trough a wire the wire will heat up because of it's resistance for electricity,...
View ArticleWhat is fugacity?
What is fugacity ? I know it the corrected pressure for non ideal systems , but I need a much more intuitive sense of the term. It would be nice to get some help on this...
View ArticleCan somebody explain boundary conditions, for normal modes, on a wire?
I don't really understand boundary conditions and i've been trying to research it for ages now but to no real avail. I understand what boundary conditions are, I think. You need them along with the...
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Why is the the first order useful?
I've been looking into diffraction for AOLM and stuff like that, and these produce diffraction. Binary Spatial Light Modulators like Digital Micromirror Devices also produce diffraction. This...
View ArticleThe gravitational field at a mass point produced by an infinite plane
I'm reading: http://www.feynmanlectures.caltech.e...3.html#Ch13-S4 1. In the link it says: ##2\pi\rho d\rho## is the area of the ring of the radius ##\rho## and width ##d\rho##, if ##d\rho \ll \rho##....
View ArticleOrienational order parameter in isotropic systems
Hi everyone, I have what may be a dummy question. In NMR or in the study of liquid crystals for example, an order parameter [itex]S[/itex] is often used:...
View ArticleJones matrix describing the action of the quater-wave plate
Hi there!!!! I am having troubles with understanding about the representation of the Jones matrix for the QWP I have the general form of the Jones matrix for the QWP: Q={{i, 0},{0,1}}. But after...
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Gravity Assist-Elliptical Trajectories
Good evening, I am working my way through a JPL technical report I found online at link Specifically, I am at page 17 which looks like and I am trying to understand the relation I basically, don't...
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Magnetic Field Reflection from a Media Interface
Say there is an electric field oriented along the x-axis and is propagating along the z-axis. A medium exists from z>0. The fields for z<0 can be written as I'm confused on the negative sign of...
View ArticleHeating a pure substance at it's triple point
Suppose we heat a pure substance in solid phase at a constant pressure corresponding to it's triple point data up to it's triple point temperature where all the three phases of the substance are known...
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