Trending questions

I don't understand why the reverse Carnot Cycle works. Let's consider the isothermal expansion of a gas (body). The gas does work, but its temperature remains constant. For this to happen, the gas ...

While deriving ideal gas equation we assumed the container to be a cuboid and then we took the volume to be $lbh$ where l, b, h are length, breadth, and height respectively. Will the equation still be ...

Acceleration involves a squared time item, and Newton's law of universal gravitation contains a product of two masses. Such mathematical expressions seem to be meaningless when taken in isolation; ...

In classical mechanics we say that a classical particle obeys the equations of motion, whereas in quantum mechanics a particle can take any path, not just the classical one. But when we quantize a ...

How do we see the observable universe? We can't use a normal telescope to see the whole observable universe obviously. So which technology helps us see the observable universe? I’m a 7th grader so ...

I'm having trouble understanding how two entangled particles stay correlated once they are measured. As an example, if they are anti-correlated in their spins, and one particle is measured to have a ...

I am currently reflecting a bit on the formal structure of the theory presented in Callen's classic text Thermodynamics and an Introduction to Thermostatistics. I was originally going to post a more ...

Reading Schutz's book on GR: On page 9, there's a derivation (reproduced in the picture below) that I don't follow. If all the barred coordinates are combinations of the unbarred coordinates, then ...

I’m a 7th grader, so I'm not good in physics that much, but I'm just a curious boy which wants to become a cosmologist. Can the amount of energy or particles run out? For example, pizza dough can be ...

UPDATE for Mods: Currently travelling; aiming for edited version over weekend 30 Nov. After reading a number of posts here in the last few years I'm left wondering why most questions about the ...

I have a few questions about principle how van de Graaff generator works. To avoid confusion I will use numbering from the wiki picture: [ADDED LATER #1] See also here for nearly identical ...

A system made of an even number of fermions behaves like a boson in terms of quantum statistics. One example for that would be the hydrogen atom consisting of one proton (spin-1/2) and one electron (...

In general relativity, the black hole region (B) of an asymptotically flat spacetime $M,g$ is defined globally as $$ B := M \setminus J^-(\mathscr I^+), $$ and the (future) event horizon is its ...

In standard electrodynamics $$\mathbf{E}=\mathbf{E}_\parallel+\mathbf{E}_\perp$$ $$ \begin{eqnarray} \mathbf{E}_\parallel&=&\frac{1}{4\pi}\int\frac{\rho}{\varepsilon_0}\frac{\hat{\mathbf{r}}}{...

Consider Compton scattering $$p_1 + p_2 \to p_3 + p_4$$ in the laboratory frame. According to Quantum Field Theory and the Standard Model by Schwartz, the relation between the differential cross ...