# Search results

1. ### Is Quantum Mechanics an artifact of our ignorance?

I've read a lot about QM and studied the math and how it work many and many times in several lectures in several places, but whenever I review what the theory says and compare it to how the measurement work, I come to doubt in the theory it self, I think it can even be explained using classical...
2. ### Electric field due to a charged sphere

Another problem that yet I haven't managed to solve, finding the electric field due to a charged sphere of radius R using integration Homework Equations Continuous charged distribution $$|\vec E| = \frac{1}{4\pi\epsilon_0}\displaystyle \int\frac{\rho (r') dV}{r'^2}$$ The Attempt at a Solution...
3. ### Electric field due to a charged disk

Homework Statement I'm reading Griffith-Introduction to electrodynamics, In chapter 2 about electrostatics, I've encounter few problems that I've managed, to solve (luck !!), I'm asked to calculate the electric field due to a charged disk of radius R in a point P above the center (Pic)...
4. ### Pole in the house

I was thinking about this for a while now but I coudn't explain it, si here is it :, We have and athlète holding a horizental 20m pole, he's moving at with a (relative) velocity v such that γ = 2, he kept until reaching a 10m large house and closed the door, the house is at rest, now for the...
5. ### 2nd Order Elliptic Equation

I've been searching for exact solution of d2y/dx2 = C/y, where C is some constant, such equation take place when deriving equation of motion in gravitationnal field, I'm more interested in how to solve it, yet I only managed to express it as power series using taylor's theorem at x = 0, just...
6. ### Relativity Special Relativity Problem Textbook !,

Hi PF, I'm trying to learn both special and general relativity, I have read all about them, learnt the basic math needed, but that was all without "enough" exercices to completely understand the theory, so I need problem books that are purely or mostly about problems about special relativity...
7. ### Fall in Space-time

Hi there, the most basic formula from newtonian gravitation is, for a free falling object, x = gt^2/2, where x is the displacement in the vectical direction, in the case of general relativity, this just happens to be for weak gravitational fields, for the sake of simplicity (trying to express my...
8. ### Relativity of simultaneity

Good morning, Yesterday I was reading a book about special relativity, It focused a lot about consequences of the theory, but there's only one thing I couldn't understand, which is as the title suggests, Relativity of simultaneity, that two different observers can't agree if two event are...
9. ### Calculus of Variation Problem

Homework Statement Determine the Lagrange-Euler equation for the functional J[y] = ∫F(x,y,y')dx = ∫F(x(y),y,1/x')*x' dx = I[x(y)] Homework Equations The Lagrange-Euler equations ∂F/∂y = d(∂F/∂y')/dx The Attempt at a Solution I'm new to the subject, so I don't really know what to do, I've...
10. ### Propability of finding a particle outside the classical limit

Homework Statement I'm asked to calculate the propability of finding a particle outside the classical limit for a quantum harmonic oscillator in it's ground state Homework Equations Ψ0(x) = a*emωx2/2hbar When a = (mω/πhbar)1/4 The ground state energy E0 =hbar*ω2/2 The Attempt at a Solution I...
11. ### Studying Physics !

Hi PF, Summer is almost here, and I've decided to use it to learn modern physics, but a little bit confused . So what is the mathematical back ground needed to learn special and general relativity ? Where exactly should start ?
12. ### Reflected and Transmitted wavefunction (QM)

Homework Statement I'm asked to calculate the reflected and transmitted part of the wavefunction, in fact, this is the first time i encounter this so i need your assistance. Homework Equations Time independant schrodinger equation + continuity condition The Attempt at a Solution See the...
13. ### Time Dilation

Hello PF, A question on special relativity I've not found an answer to,I tried to google it but no luck, so here is it : If you were to observe a moving body whose speed is very near to the speed of light, will you see it slowly due to time dilation, or you'll observe it as it really is, very...