I have noticed clouds appearing black during rain. But I don't know what makes clouds to acquire that colour. This phenomenon doesn't appear every rainfall. There has to be distinction to white ...
I've read on the Internet that wearing plastic shoes doesn't allow electric charges we collect from our environment (PC, TV, appliances) to be earthed. Is this reasoning correct?
Is putting a charged balloon up to a neutral wall polarization AND temporary induction, or just polarization?
Is putting a balloon that is charged up against a wall and having it stick polarization AND charging by temporary induction, or just polarization?