Super Fantastic Ice Melting Apparatus Expedition
By Charlie Ford & Travis Gamache
Table of Contents
Introduction Problem Review of Literature Hypothesis Materials Set-up Procedure Data & Graphs
Visuals of Tests Conclusion & Analysis Related Links Bibliography Return To Research
Everybody knows that ice melts when temperatures reach 32 degrees Fahrenheit or higher. But can adding weight to the ice affect how it melts as well? The weight affecting ice melt can be seen in many different things, such as glaciers. According to one website, “ As snow layers accumulate and gather weight, the pressure builds up on the bottom layer. This causes the bottom layer of ice to melt and it becomes soft and pliable. The melting of the ice due to pressure and its refreezing is called regelation”(https://www.cresis.ku.edu/education/iibLessons/iib009.pdf). The somewhat melted ice gets pushed out to the edges and the glaciers moves a little bit thus continuing regelation. Pressure Melting causes the ice to melt. The Pressure Melting point is when the pressure on the ice is so great that it eventually ends up melting the ice. LeChatelier’s Principle is a good example of this, it states, “that when a system is in equilibrium, any external changes that try to take it out of equilibrium will cause the system to adjust in a way to counteract that change” (Nelson 2007). This is like applying weight to ice. Water fills a smaller volume than ice, so it lowers its melting point allowing more ice to become liquid filling in the extra space. Studies have shown that a certain amount of pressure can cause pieces of ice to start melting.
The purpose of this experiment is to find the relationship between the amounts of weight added to a copper wire resting on a piece of ice and the time it takes to cut through the ice.
Brent Nelson a Ph.D. Student at UC Berkley states, “If you increase the pressure on the ice the ice-water system wants to try to lower it again. It can do that by making itself fit into a smaller volume. But since water fills a smaller volume when it's liquid, rather than solid, it will go to a lower melting point -- allowing more solid to become liquid” (Nelson 2007). Because of this we believe that if the ice is being pushed on with a weighted wire that the ice is going to end up melting because its going to be splitting the ice and its going to melt to fill in the gap the wire has created.
Also thanks to the studies from, Drake, L.D, and Shreve, R.L we know that, “The motion of wires pulled transversely through ice has long been explained in terms of pressure melting at the front of the wire and regelation behind it, the speed of the process being controlled by the rate of conduction of the heat of fusion through the wire and the ice”(Drake, Shreve). Because of this we learned that the weight from the wire would cause the ice to cut in half do to pressure melting. We also learn that refreezing of the ice behind the wire is called regelation.
Cresis.ku.edu also goes into some detail about this idea of regelation. It is something that occurs often in glaciers while they are moving. The website states, “ As snow layers accumulate and gather weight, the pressure builds up on the bottom layer. This causes the bottom layer of ice to melt and it becomes soft and pliable. The melting of the ice due to pressure and its refreezing is called regelation”(https://www.cresis.ku.edu/education/iibLessons/iib009.pdf). This information tells us that the wire should be somewhat frozen into the ice after it has cut partially through the ice.
Overall the wire should cut through the ice due to weight causing pressure, which will melt the ice due to pressure melting. The wire should also be refrozen into the block of ice due to regelation.
Beam Me Up
We believe that graphically (with mass as the independent and the time it takes to cut the ice cube as the dependent) our results will be a downward slope. The more mass added to the wire the more quickly the ice will be cut. We will only go so high in weight because eventually the ice cube won’t be able to take the weight and our data will not be accurate.
The Materials we used were: a piece of wood approximately 10 ½ inches long, another piece of wood approximately 5 ½ inches long, a strip of 2mm copper wiring,
a Malleable Iron Vice Clamp, multiple Duralex LYS Small Glass Bowl (Or something similar), 1 Teaspoon, water, a freezer, a stopwatch, 2 screws, 4 2.5lb weights, 2 5lb weights, 2 10lb weights, 1 hook screw, a saw, some sand paper, any bowl to catch the water drops, and a room at a constant 69 degrees Fahrenheit.
We used four of the same Duralex Small Glass Bowls to ensure that each ice cube was almost exactly the same in size. We filled each one of these glass bowls up with 6 teaspoons of regular tap water. This would also ensure that the water would expand similar and there would not be any huge differences in our ice cubes.
We also found an area that was not affected by any drafts of wind and the room temperature was able to be measured and would be the same through out the test. We used a room that was around 69 degrees the whole time to make sure that the room temperature did not affected the melting time of each ice cube.
For the apparatus itself we used two pieces of wood. One piece was approximately 10 ½ inches long while the other one was 5 1/2 inches long. We also used a piece of copper wiring. This can very in length because it does not affect the cutting through the cube. However, it has to be short enough that the second piece of wood is not touching the ground. We then proceeded to screw two holes in the shorter piece of wood approximately 1 inch away from either side. After this we screwed the screws into the bottom of the piece of wood and half the screw was still showing (the length of screw showing will vary upon the length of your wire). After this we screwed another hole in the middle of the small piece of wood again and put a hook screw in the bottom of it to hang the weights. We then screwed holes completely through the smaller piece of wood to allow the cooper wiring to attach to the screws. We then wrapped the remaining copper wire to the exposed screw heads and now he had the smaller piece of wood dangling from the copper wire. This would give us somewhere to put the weights.
Now with the larger piece of wood we cut two slits width wise approximately 2 inches in from the end. This allowed a place for the copper wire to hang. Make sure that the slits are not to close; otherwise, the piece of wood could break under the weight (slits can vary in width and length they just have to allow the wire to be able to cut through the ice). We then sanded down the middle in between the slits to make sure that the wire could cut completely through the ice block. This also made it easier for us to tell when the wire had cut through the ice. We then vice clamped the piece of wood to a sturdy surface and hung the apparatus up. We then added different weights to the bottom piece of wood. Then we took a piece of ice out of the freezer and draped the copper wire with the weights on the bottom over the top of the ice cube and recorded how long it took to melt the ice with each weight.
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First read the set-up to learn how to build the apparatus and freeze the ice. Then start off with two trials with no weight and only the wire draped over the piece of ice to get a control time. Proceed by starting with 2.5lbs and time how long it takes the weight to cut through the ice block in a 69 degrees Fahrenheit room. Do this twice. Then add another 2.5lbs so it is at 5lbs and time how long it takes 5lbs to cut through the ice. Do this twice as well. Then create more ice with 6 teaspoons of water in the Duralex containers and let it sit in the freezer for 45min to 1hr depending on the temperature of the freezer (just make sure the ice is solid). Then add another 2.5lbs to the 5lbs making this weight 7.5lbs and time how long it takes this weight to cut through the ice. Do this test twice as well. Keep adding 2.5lbs to each previous weight until 22.5lbs having two trials for each weight and repeating step 4 whenever you run out of ice.
