when I look up into the night sky I see planets, not twinkling like the other stars, but still illuminated. However, when the Hubble or James Webb telescopes approach planets we see the local features instead of an illuminated sphere in space. why is that?

In the physics book by Resnick Halliday Krane, Chapter 3, there was a statement which confused me... To test whether a particular frame of reference is an inertial frame, we place a test body at rest in the frame and ascertain that no net force acts on it. If the body does not remain at rest, th...

I am reading John Bell's article On the Einstein Podolsky Rosen paradox and I am confused by the following sentence in the beginning of part III: Suppose we have a spin half particle in a pure spin state with polarization denoted by a unit vector ... What does Bell mean by polarization of spin ...

In the diagram above, person $P$ is pulling block $B$ by a massless rope $R$, and they are all accelerating in the indicated direction. If the force that $P$ applies to $R$ is $F_{P,R}$, then to my mind the force $R$ applies to $B$, $F_{R,B}$ is such that $F_{P,R} = F_{R,B}$. By Newton's Thi...