This is a simple question that’s been plaguing me for a bit, but which doesn’t seem to have been covered in my basic physics class. Say you placed an object on a table. The object would feel a gravitational force whose magnitude is dependent upon the object's mass; however, in order for the...
I’ve heard that the reason radio telescope dishes can be made out of wire mesh is because, so long as the size of the holes is less than (I believe) 1/10 the wavelength of the radio wave, the wave be reflected (it will see the dish as being solid). I was wondering what the physical reason was...
"Bottom" limit of telescopes
I know this is a very elementary question, but I was never quite able understand why there was a bottom limit to what telescopes could "see". For example, I have not quite been able to grasp why telescopes can only see in the radio, but are invisible to optical...