Why does atmospheric pressure decrease with altitude? A6. There are fewer air molecules above you as altitude increases, so the weight of the air column decreases.
Why does a ship float? A9. The ship displaces enough water so that the upthrust equals its weight. aqa science p2 5.5 activity sheet answers
What is upthrust? A8. An upward force exerted by a fluid on an object immersed in it (caused by higher pressure at the bottom of the object than at the top). Why does atmospheric pressure decrease with altitude