Alexis

I agree with Caiti. I don't think there is an "ultimate" frame of reference. I think different points of view are necessary in different situations. For the most part, I think the Earth is the best frame of reference for most of the measurements we make here on this planet. Newton's Bucket shows this, because after you stop spinning (and even when the bucket itself is spinning) we say it's spinning in comparison to Earth, not the bucket. In the moment both bucket and water are spinning, it doesn't seem like the water is moving relative to the bucket.