melts,the level of water will:
1)go down 2)firsst go down and then go up 3)remain the same 4)go up
the right answer is option 1).. i dunno the reason
2006-10-21 01:31:35 · 8 answers · asked by tut_einstein 2 in Science & Mathematics ➔ Physics
there is nothing wrong with the question. let me explain.
first you have to know that when floating ice melts, the water level will not change. because when ice floats, it displaces its weight in water, not volume, so its expansion upon freezing does not affect the answer to the question.
there is some leadshot in the icecube. the fact that the icecube is still floating confirms the flotation principle. ie, the weight of the water displaced is the weight of the leaded ice.
now when the ice melts, the melted ice flows back into the water. remember, there is no change to the water level......yet.
what happens is that the leadshot start to sink, so the flotation principle is no longer applies to it. now the lead displaces water equal to its volume not weight. since lead is much denser than water, the amount of water displaced by lead's volume is less than the amount of water displaced by lead's weight. so when the lead starts to sink, to begins to displace less water.
since all the water is contained in a vessel, lesser displacement of water means the water level falls.
2006-10-21 02:02:26 · answer #1 · answered by Anonymous · 2⤊ 1⤋
It might help to "reverse engineer" the problem. Start with a vessel containing ice water, floating ice and a large lead shot on the bottom. Mark the water level. If the ice melted the level would not change because ice displaces its own weight in water and melts to exactly fill the "hole" it makes in the water. However, if you lift the lead shot and hook it to the bottom of the ice, it will pull it down displacing more water and raising the water level while the lead displaces the same amount of water. Mark the new level. When the ice melts (releasing the lead) the water level will return to the original lower level. In your problem the lead is encased in ice rather than hooked onto it but the effect is identical.
2006-10-21 02:25:03 · answer #2 · answered by Kes 7 · 1⤊ 0⤋
There is something wrong with the question.
It should be either option 3 or 4. True, ice does expand when frozen, but the lead shots should displace the water in the vessel, and affect its level...
2006-10-21 01:43:04 · answer #3 · answered by khall 2 · 0⤊ 1⤋
Water expands when it freezes. The ice is not floating in the water ( by virtue of the leadshot) but is fully immersed in the water.When the ice melts it loses volume and so the water level goes down.
2006-10-21 02:14:55 · answer #4 · answered by sydney m 2 · 0⤊ 0⤋
Say the lead weighed a pound. When it was in the ice and floating, it displaced a pound of water. Thank you Archimedes. When it's on the bottom it only displaces it's volume in water, which would only be about two ounces of water displaced.
2006-10-21 09:20:24 · answer #5 · answered by Nomadd 7 · 0⤊ 0⤋
When it is frozen water expands. As the weight of the lead shot(s) is already in the water, it will make no difference. Therefore the water will lessen in the vessel.
2006-10-21 01:36:19 · answer #6 · answered by Beau R 7 · 0⤊ 0⤋
The correct answer should be 3)
I think there must be an error in your source
misprints in books are quite common.
2006-10-21 01:40:08 · answer #7 · answered by ? 5 · 0⤊ 1⤋
water expands when its frozen ... thats all to it
2006-10-21 01:33:18 · answer #8 · answered by Anonymous · 0⤊ 1⤋