Image from object at a focal point of mirror
Hi all, If I place an object far away from a converging mirror or lens and start to move it closer, I note that I get an inverted, real image that steadily grows in size. As the object crosses the...
View ArticleWhat is Gravity?
I have been wondering about this for a while! What exactly is GRAVITY? How does it work?? How are things pulled towards the earth? or any other mass?? So I came up with a kind of a theory about this!...
View ArticleAtmosphere modelling
If g (acceleration due to gravity) was double on Earth, how tall would our atmosphere be?
View ArticleRelationship between intutions on energy
Hi all, After reading Feynman's Lectures I see that his way to understand energy is as a conserved quantity. On the last days then I've seem Susskind's lectures on classical mechanics and he also...
View ArticleFocusing sound waves
Can we focus parallel sound waves using convex and concave lenses since they essentially follow the same laws of refraction as light? If not, is there any way to focus parallel beams of sound to...
View ArticleCoefficient of Static Fraction
Please could somebody explain how the coefficient of static friction can be quoted as a constant in tables etc? [itex]\mu_s = F_s/ R[/itex] In most cases the reaction force is constant but as I push...
View ArticleOptical Transfer Function of a microscope
Hi all, I have a question about the "missing cone" problem in wide-field microscopy. The Fourier equivalent of the PSF is the OTF. The OTF has a toroidal (doughnut) shape. I'm a little confused by how...
View ArticleWhat concept does work formalize?
Hi all, Well, I'll try to explain my doubt with an example. The idea of force formalizes what we intuitively think as a push or a pull, torque formalizes what we think as a turn, linear and angular...
View ArticleHow constant acceleration affects the tripulation of a spaceship?
I appologize for any spelling or grammar errors. Please take into account that English isn't my first language and that I haven't finished my English course yet, since I'm 14 years old. My Question...
View Articleaxis of rotation
Does a body rotating about an axis also rotate about any other axis? Eg. Cars on a racetrack may be rotating about a vertical axis passing through the centre of the track but can they also be...
View ArticleSpherical capacitor and vector potential
There is a spherical capacitor with inner and outer radii of a and b respectively,has a dielectric material of small conductivity [itex] \sigma [/itex] between its concentric conducting...
View Articlelinear and angular momentum
Hi, I,ve been looking through some notes on Lagrangian mechanics but they have got me confused so i'll start from the beginning. If a point mass is moving in the x-y plane with constant velocity v at a...
View ArticleHamilton Equation and Heisenberg Equation of Motion
I was given the (general) following form for the Hamilton and Heisenberg Equations of motion [itex]\dot{A}[/itex] = [itex](A, H)_{}[/itex], which can represent the Poisson bracket (classical version)...
View ArticleHeat flux on a cylinder with two insulators
I'm used to problems which ask me to find the heat flux for when, for example I have a very long cylinder covered with an insulator, each with their respective conductivity coefficient. I'd use the...
View ArticleCurrent loops and electric dipoles
Hello Physics enthusiasts Imagine an infinitesimal small current loop where the current can run clockwise or counterclockwise at frequency v. I am trying to find a linear combination of the two(current...
View ArticleStokes' Theorem Proof?
How would one prove Stokes' Theorem? I'm 15. I learned about Stokes' Theorem recently and I have a decent understand of it, but I thought that it would be useful to know it's derivation. Thanks for...
View Article2-Body Lagrangian problem
I have been looking at the problem of 2 point masses connected by a spring in polar coordinates. The problem is solved using the center of mass coordinate R and the relative coordinate r where M=total...
View ArticleInterference
When you shine light on a mirror perpendicularly. Does the reflected beam then not interfere with the incoming one? With my intuition it would, and the interference would oscillate between destructive...
View ArticleNet force on a Swinging Pendulum
Hello everyone, Consider a weight tied to a string spinning in a horizontal circle. According to Newton's third law, the force of the string on the weight (inward) is opposite and equal to the force of...
View ArticleModifying the heat equation for multiple sources
If I have a hot wire, the distribution of its temperature with respect to radius (from the center of the wire) and time follows the heat/diffusion equation. However, now consider two wires, or even an...
View Article