Electrostatics & Quadric Surfaces
Hey guys, I'm in some serious trouble - I don't know how to solve a lot of problems in electrostatics. The main reason is that once I seen that you had to be able to find electric fields & electric...
View ArticleThe Motion Of Objects Thrown Away From Earth
How can the function for distance over time be found for an object which is thrown away from Earth? Acceleration as a function of distance is g = GM/r^2, where GM is constant, so let c = GM, then g =...
View ArticleWhat could cause a polarizer to not block 100% light?
i have a cheap polarizing shade i bought from walmart. i aligned my polarizing shades with the polarized light coming from my laptop, however not all the light was blocked. just to be extra sure that...
View Articlehow does wave reflection work?
this is a silly question but, how exactly does the reflection of a wave work? explain to me the mechanics/physics please. say you have a rope attached to a wall at one end. and at the other end there...
View Articlehow does a two open ended pipe resonate?
For a pipe with both ends closed, with sound being produced from one end, sound is reflected off of the other end and is able to produce a standing wave, however, for pipes with both ends open or one...
View ArticleMechanics of a falling slinky
So I saw a video of a falling slinky in slow motion where a slinky is held at the top and is let to be stretched by gravity until gravity and spring pulling force equal out, when the top is let free,...
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General equation for light intensity entering half circle
Hello, I am currently working on a problem to calculate the light that makes it through a half circle. For example, say I put a cylinder out in the sun, where the intensity is known to be 1030 W/m^2. I...
View Articlewhat is the amplitude of an EM wave?
i always hear about the frequency/wavelength, and the speed of the wave, but i never heard about the actual amplitude of the wave itself? how would one derive this? i'm not referring to intensity........
View Articlehelp with derivation of torque equation T = p x E
[itex]\vec{\tau}[/itex]=[itex]\vec{F}[/itex]x[itex]\vec{r}[/itex] [itex]\vec{F}[/itex]=[itex]\vec{E}[/itex]q [itex]\vec{p}[/itex]=q[itex]\vec{d}[/itex]...
View ArticleFluid mechanics, source-sink question
In fluid mechanics, the velocity of the liquid going in or out (source-sink) of a hole in a two dimensional model is Q/(2 pi r). http://farside.ph.utexas.edu/teachin...ml/node63.html What is the...
View ArticleConfusion over Pascal's Experiment
I have been trying to understand pascal's barrel experiment in a more qualitative sense but I can't get my head around it at all. Pascal supposedly had a strong wooden barrel which he attached onto it...
View ArticleWhy are Normal forces not constant?
If I put a 1 kg mass on the floor, the floor exerts a 10 N force on it, balancing gravity. If I then replace that mass with a 10 kg one of the same area, the floor now exerts 100 N on it. What is it...
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Please help me understand these equations
hi everyone! i'm trying to learn angular dynamics from this document: http://chrishecker.com/images/c/c2/Gdmphys2.pdf I believe i'm understanding it all pretty well so far, but i come to a stumbling...
View ArticleIs this a correct derivation of Moment of Inertia?
Hello everybody! This is the derivation (for a single particle). [tex] \tau = F_{\perp }r \ = ma_{\perp}r \ = \alpha mr^2 \\ \text{if }\ \tau = I\alpha \text{ where } I \text{ is resistance to...
View Articlemechanics of double helical gears
Hi: according to the wikipedia page: https://en.wikipedia.org/wiki/Gear#Double_helical the unstable and stable configuration would disassemble and correct the axial misalignment respectively. I...
View ArticleThe concept/signifacance of electric/magnetic moments
Hello, I would like to know what exactly the concept is behind electric/magnetic moments. Just to give a little context, I'm currently doing an internship for the summer and my research deals with...
View ArticleIs a Gaussian surface truly arbitrary ?
Consider a point charge q at the vertex of an arbitrary cube. If asked to consider the flux the cube experiences, q/8epsilon seems a natural answer, by constructing seven more such cubes to create an...
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Calculating Ixy ?
Here as shown in the diagram, (1)Is Ixy zero for plane ABCD symmetrical along X axis? If yes, how it happens? (2)How can we calculate Ixy for the plane PQRS ? Ixy = the product of moment of area....
View ArticleCherenkov radiation - phase velocity not group velocity
Why must the charged particle that leads to Cherenkov radiation travel faster than the phase velocity of light not the group velocity of light? One of the sides of the triangle that is used to define...
View ArticleElectric field of a spherical cap
Hi I am looking for the electric field caused by a uniformly charged spherical cap. Actually, I need only the potential inside the sphere. Is there anybody who knows how to do this. Frankly, I do not...
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