12:33 AM
1

Torque and energy have the same dimensionality, and so logically are measured in the same units (joules). However, it seems more natural to call the unit for the former a “newton-metre”, because torque does not feel like a form of energy, even though this elaborately described unit means no more ...

17 hours later…
5:12 PM
1

Let's use the spherical coordinates so that $\vec P=(r, \theta, \phi)$. In this context i've read that it's possible to write $$\vec P'=\vec P + d\theta\ \vec e_\theta+d\phi\ \vec e_\phi+dr\ \vec e_r$$ but i don't understand the meaning of this since it looks like (r', \theta', \phi')=(r, \thet...

3 hours later…
8:15 PM
3

I was studying particle physics and I saw the word "scalar particle" many times, also in books. On the internet there wasn't any thing about it. So can anyone say what is a scalar particle ?