two musical dynamics questions

[40yrslater]

It's been 40 years since I played the piano and, amazingly, most of it is coming right back to me - I'm happily playing 5 flats etc.  My interests are solely in classical music and I'm working up some great pieces.  HOWEVER....I don't recall some technical details (or never learned them).  Today's questions:
1) When it says "p" or "f" etc.....does that dyanmic continue until a different one is shown?
2) When the, let's say "p," is below the bass clef, does mean it ONLY applies to the bass clef? and if it's right up under the treble clef only to that clef? and, if it's in the middle of them then it applies to both clefs?

Thanks for answering - and I'm sure I'll have many more

[thinkgreenlovepiano]

Well since no one answered you yet, I'm going to try. I hope it makes sense, but I'm not a professional pianist or anything...  But I'm sure someone else will come along and clarify...

1) I think this depends... sometimes it sounds better to suddenly change the dynamics, other times its better if its gradual and you would use crescendos and diminuendos. Or you might add in your own dynamics, sometimes music scores have almost no dynamics but that doesn't mean you don't use any. Also you have the think about the phrasing and all that.
2) Yes, but just because its in the middle doesn't mean that both hands are necessarily played with the same dynamics.