I've been told that it's much harder than AQA A. Personally, I have no way of proving that as I've only ever done AQA B. There is a huge step up from GCSE in terms of content in this specification as they start with arguably the hardest topics. There is definitely more formulas to use than at GCSE for AS but they actually tell you what they are used to work out at AS as opposed to GCSE where you are somewhat left in the dark. I would say you either need to have a good ability with algebraic manipulation or learn fast if you want to understands many of the physics or equations in this specification. This is because this specification in actually more theory heavy than the others. As such, the maths needs to be applied to specific situations and you need to understand what is going on to work out what you need to do.
So, to answer your question, maths does play a large part in AQA B. However, the theory is arguably more important.