"was being verb+ed" The action continued/was in progress in the past. "was verb+ed" The action finished/stopped in the past. We don't know if it continued or was in progress. Both are passive forms.

was being physically abused : it is a passive form of past continuous tense was physically abused : it is a passive form of simple past tense

This is a difficult question but I'll give it my best shot. Ex: I was being pushed around when my parents showed up at the school. This sounds like bullies were pushing you around and then your parents showed up and saw it. Ex: I was pushed around when my parents showed up at the school. This sounds more like bullies pushed you around because your parents showed up at school or even that it was your parents who pushed you around. "was being verb-ed" sounds like an action had been occurring for a while and that it wasn't caused by something else in the sentence. "was verb-ed" sounds more like something happened only once, or that the verb was the result of something else in the sentence. I hope this helps. Best of luck and keep studying!