Hi! I wonder if there was any experimental measurement of magnetic field produced by mechanically moving charges. In principle the equation is well known. (1) But is there any experimental proof of this equation? I know it can be reformulated into this. (2) My question is "Is there any experimental proof of Eq. (1)?" I guest particle accelerator level experiment would create detectable magnetic field. I read lightning magnetise things, but it is not a direct measurement. Please let me know if there is any DIY level experiment of measuring magnetic field by mechanical movement of charges. If it is not possible, could anyone explain why? Thank you in advance!