A uniform magnetic field doesn't apply any magnetic force to a stationary charge but a changing magnetic field does, why?

Question

I recently studied that emf can be produced in two ways, one is motional emf and it's reason is quite clear, but the other one is hard to understand, our teacher told us getting the actual picture of what's happening requires the study of some higher theories, so I would like anyone to give me what is the actual picture (you can use relativity, elementary particle model, etc)