Thread: Pool Physics

Ok, I had a wieght question. If you are in a pool, and the entire pool weighs 8 tons and you weigh 200LBS. If you jump in the pool and go completely underwater, how much would the pool weigh? I may just be asking common sense, but I know if you go underwater, you are pretty much 99.99% weightless, or gravity-free. I figure if you're half in the water, and half out of the water, it might weigh more, because you are floating on the surface, since the surface has the effect of gravity (OBVIOUSLY...). If anyone could answer this, please help, becuase when I get puzzled, I STAY puzzled . Thanks for all your help everyone!

The pool weighs 8 tons. You weigh 200 lb. You plus the pool weigh 8 tons plus 200 lb, whether you are in the pool or not.

No matter how you move?

Let's say the pool is sitting on a truck scale and weighs 8 tons. When you jump in and hit the water you will be decelerating. The scale will read 8 tons+200lb + some additional amount equal to the force that is causing you to decelerate. When you come to a stop, either above water or under water the scale reads 8 tons+200 lb.

Oh ok. Well thanks for your help

It might help to realize that when you are submerged, you are not weightless. You weigh the same amount as ever, but your weight is supported by the buoyant force of the water pushing up on you. This weight is added to the reading on the scale.