I think electrons will be pushed against the flow of current towards q, with the large resistance from the voltmeter stopping it there, so the electron will bunch up there making it negative and so p is positive
oh yeah thanks, i was more asking if you can 'get rid' of products in a dot product when they are equal to zero though, just because the solution just expands it instead
(the red arrow) In vectors are you allowed to just factorise out something when it equals to zero like in algebra, because the solution expands it and then equates them, so is my way wrong?