We talked about this is an old physics class of mine but I can't remember the explanation now: There's a stationary boat in a lake carrying an object (an anvil, say). I want to know what happens to the water level (height) when the anvil is thrown overboard.
What are the variables we have to look at? I'm thinking just the volumes: V1 of the boat and V2 of the anvil. Do we have to consider H20 density and/or weights of the boat and anvil? I seem to remember my teacher saying the water level of the lake will always do one or the other (rise or fall) no matter what. Is it that the level will always rise because the added volume being submerged displaces more water? But then there's less displacement when the boat rises, right? Arrgh...I'm not a scientist, but I'd really like to figure this one out :-)
Thanks in advance
Levi
2006-08-20 09:36:18 · 11 answers · asked by levi_denham 1 in Science & Mathematics ➔ Physics
Archimedes' principle--the weight of a floating object is equal to the weight of the water it displaces. Hence the anvil when floated will displace its own weight--otherwise it would accelerate up or down.
The anvil in the water, at the lake bottom will displace its volume in water. Since iron is denser than water, the volume of water equivalent to the volume of the anvil is less than the weight of water equivalent to the weight of the anvil. Hence less water is displaced, and the level of the lake will drop a little bit.
2006-08-20 10:14:55 · answer #1 · answered by Benjamin N 4 · 1⤊ 1⤋
The weight of the boat including the anvil is already displacing a certain volume of water and made the water level rise when they entered the lake. So, the anvil has already increased the level of the lake while it is in the boat. You got it when you said the boat will rise displacing less water when the anvil is thrown in. Therefore there will be no change.
2006-08-20 09:53:03 · answer #2 · answered by Wascal Wabbit 4 · 1⤊ 0⤋
no change. When you sail out on the boat with the anvil on board, your combined mass will displace an equal amount of water. Throw over the anvil, the total mass and dispaced water is the same, it's just what's displacing it is in a different place.
Of course when you take the boat out of the lake, the level will go up by the displaced volume of the anvil compared to where the level was before you launched
2006-08-20 09:49:27 · answer #3 · answered by perk 2 · 1⤊ 0⤋
wow--only two guys got his one right. The lake level drops for the reasons provided above. Here's a simple way to think about it--once the anvil is in the water, its weight becomes irrelevant and only its volume matters. When it's in the boat, only its weight matters and its volume is irrelevant.
Here's one that's a lot more interesting--small glass full of water sitting in a pie tin, which is floating in a tub of water. Pie tin and glass upset and go to the bottom of the tub. Now what happens to the level in the tub?
2006-08-20 15:10:32 · answer #4 · answered by Pepper 4 · 0⤊ 0⤋
The level goes down.
When the anvil is in the boat, it displaces a volume equivilent to its weight in water. Since water is less dense than the anvil, that is a bigger volume. When you throw it overboard, it only displaces its own volume which is less, so the water level drops.
2006-08-20 09:41:23 · answer #5 · answered by Anonymous · 4⤊ 1⤋
the point of the water continues to be an analogous because an analogous quantity of weight remains interior the lake. The boat will opt for the flow a touch more beneficial larger interior the water because it now weighs a lot less.
2016-11-05 06:13:50 · answer #6 · answered by ? 4 · 0⤊ 0⤋
it would only displace water if it was thrown from a dock or somthing because the boat is already displacing the water dependent uppon the weight of the objects inside of it.
2006-08-20 16:03:24 · answer #7 · answered by angel_of_death_32x 1 · 0⤊ 0⤋
assuming the object thrown overboard is denser den water, the water lvl will actually sink. to put things simply, when the object is on board, it causes the displacement of water to be equal to its mass. However when thrown into water, the displacement is only equal to its volume. Since its denser than water, its water displaced dats equal to its mass will be more than water displaced dats equal to its volume. hence water lvl will fall
2006-08-20 16:55:07 · answer #8 · answered by ThoughTs 2 · 0⤊ 0⤋
Like it expained huh? Try the navy or maybe dock workers.When that same boat is tied up to the dock and the water line is at one meter, then the tide drops one meter,where is the water line at that point?
2006-08-20 10:03:50 · answer #9 · answered by Anonymous · 0⤊ 0⤋
the boat gives pressure and the water level grows.
2006-08-20 09:44:12 · answer #10 · answered by Anonymous · 0⤊ 1⤋