alright, a friend of mine and I were talking about the weight of things in water. If you have a tank full of water and it wieghs lets say 100 lbs, and you add 1 fish weighing 20 lbs does the weight of the fish register? Would the total weight be 120 lbs or would the weight of everything remain at 100 lbs?
physics question
- Thread starter dr_sudz
- Start date
Well let's add a wrinkle: how much water would spill? Is it 20lb (the weight of the fish)?Yep. It would add to the total weight.
UNLESS,
The tank was completely full to the rim and adding the fish displaced some water.(that would be a heavy fish)
Then you could subtract the weight of the water displaced.
yes adding a 20lb fish will add 20lb to the total weight
and
no, the equivalent weight of the fish in water will not spill, however the equivalent surface area of the fish will spill.
Eg: The area that was filled with water that the fish now occupies has to go somewhere...
and
no, the equivalent weight of the fish in water will not spill, however the equivalent surface area of the fish will spill.
Eg: The area that was filled with water that the fish now occupies has to go somewhere...
That would be volume, not area. certainly not "surface" area.
Even if you fill a ball with air, it will weigh more than an empty ball, but then why does the scale ever read zero if there is allways air?
Even a floating ball will add to the total weight of the tank, by the weight of the ball & the air.
Now; here is a stumper question for you.....
If you suspend your (10 lb) arm in the water without touching the tank (only water), will that add to the weight of the tank? If so, how much? If not, then when you grab the 20 pound fish in your hand does the weight go back to 100 lbs? (even with your arm still inside) hmmmm....
Come on CHOMPERS this one is for you
just cause I like you.
It wouldnt be 20lbs. Thats 1/5 of the total weight of the water. It depends on how much surface area and how much the fish displaces. If you put a small dense 5lb fish in it would displace less than a 5lb puffer fully puffed.
That would be volume, not area. certainly not "surface" area.
Even if you fill a ball with air, it will weigh more than an empty ball, but then why does the scale ever read zero if there is allways air?
Even a floating ball will add to the total weight of the tank, by the weight of the ball & the air.
Now; here is a stumper question for you.....
If you suspend your (10 lb) arm in the water without touching the tank (only water), will that add to the weight of the tank? If so, how much? If not, then when you grab the 20 pound fish in your hand does the weight go back to 100 lbs? (even with your arm still inside) hmmmm....
Come on CHOMPERS this one is for you
Your arm, just like the fish, would add weight to the tank. The part of your arm that is touching the water exerts forces on the water and then these are then exerted onto the tank.