Project Design Plan Essay Example for Free

Project Design Plan EssayThis prove is to test the theory that the temperature of weewee affects the duration of m it sign ups to pissing to reach freezing? Hot water freezing sudden than cold has been observed for many centuries. The earliest known reference to this effect is by Aristotle, who wrote The fact that water has previously been warmed contributes to its freezing quickly for so it cools so 1r. Hence many people, when they lack to cool scorching water quickly, begin by putting it in the sun. . . (Jeng)Literature review1. fit in to a study of the Mpemba effect by Monwhea Jeng Many factors impact water as it cools and eventually freezes, vaporization can contribute to a loss of mass, Hot water can hold less turn gas than cold water and large amounts of dissolved gas escape upon boiling, convection currents and non-uniform temperature distribution happen as water cools, the milieual of the hot take alike impacts the environment around it. Super cooling white thorn also have an important role in the effect, super cooling occours when water freezes not at 0c but at some lower temperature. (Jeng, The Mpemba effect When can hot water freeze faster than cold? , 2006)2. In 1963 a student named Erasto B Mpemba noticed that placing recently a recently change state mixture of milk and sugar into the refrigerator it froze into ice-cream faster than an new(prenominal) students mixture that was not heated. He asked his physics instructor why this had happened and his physics instructor informed him you are confused, that cannot happen this response highlights the need for objectiveness in scientific studies. After repeatedly asking various instructors to explain his observations Mpemba took two 50ml beakers and filled one with water from the tap and one from hot water from a boiler and put them into a deep-freeze, after an hour he discovered that their was in fact more ice formation in the model from the boiler. Dr Osborne visited the school wh ere Mpemba studied and Mpemeba asked him to explain the effect, he could not but unlike previous instructors and peers Dr. Osborne conducted experimentations and did infact repeat Mpembas discovery (Osborne)VariablesThe Dependent variable is the starting temperature of the water being endued into the freezer. The Independent variable time elapsed until each sample freezes The Controlled variables are temperature of the freezer, the volume of the water samples and the sample containers.HypothesisMy supposition is that the hot water will freeze in a shorter elapsed time than the cold water due(p) to a combination of loss of volume during the heating/cooling process I arrived at this hypothesis through researching the Mpemba effect and reviewing the results of other experiments. experimental designAfter reading multiple possible slipway to conduct experiments on the Mpemba effect I chose this design plan because the experiment could be conducted with supplies I had on hand and sh ould be easily reproducible. I will measure the temperature with a common digital kitchen thermometer every(prenominal) fifteen minutes until the water sample has frozen solid generous that the thermometer cannot penetrate the ice to take measurements. The tools I will be using are 1 Plastic measuring cup,1 Thermometer, Two .30 l plastic storage containers,1 Kitchen timer, 1 Clock, 1 Range cook top, 1 Sauce pan.Threat reduction to Internal ValidityTo reduce the threats to internal validity I will use the akin affairs to objectively measure the variables of temperature and volume in my experiment. Each temperature reading will be taken using the uniform thermometer each volume measurement will be taken using the same measuring cup. Identical storage containers will be used to store the water samples and they will be placed at the same time into the same freezer on the same bare shelf. Experimental procedure.measure 1 Draw two samples of tap water 250ml each and record initia l temperature Step 2 pour one sample into sauce pan heat to boiling pour other sample into .30 l plastic storage container Step 3 pour boilingsample into measuring cup and note any loss of volumeStep 4 return samples to .30l plastic storage containerStep 5 measure temperatures of boiled sample and fashion temperature sampleStep 6 place some(prenominal) .30l plastic storage container into freezerStep 7 measure temperature of both samples every 15 min logging results until both samples are held at or below zero degrees Celsius long enough that the thermometers temperature probe cannot pierce the surface of the sample. .Step 8 Allow both samples to thaw at room temperature and measure for any loss of volumeExperiment ResultsIn my investigation the boiled sample of water did in fact freeze faster than the colder tap water sample the greatest temperature differential during my experiment arrived in the first 15 minutes of the boiled sample being introduced to the freezer, the boiled sa mple entered the freezer at 99.6C and 15 minutes later the temperature was 18.1c this represents a reduction of 81.5 degrees. No notable change of temperature to the environment was recorded. The cold sample also experienced the greatest reduction in temperature in the first 15 minutes of my experiment with a starting temperature of 14.3c and 15 minutes later the temperature was 2 degrees CelsiusThe hot sample continued to lose heat faster than the cold sample until 120 min into my experiment where both samples reached -0.6c and were too solidly frozen to continue measurements.After both samples were too solid to continue measurements I removed both samples from the freezer and allowed them to thaw once both samples were thawed I measured the be water volume the hot sample lost 30% of its volume whereas the cold sample had alone lost 10%ConclusionThis experiment has proven my hypothesis the hot water sample did in fact freeze in a shorter elapsed time than the cold water. The hot sample also lost 30% of its volume. The experimental design was a key factor in proving my hypothesis as it controlled many of the variables that could impact the outcome of my investigation. To replicate my experiment you will need a thermometer 500ml of water, two undistinguishable storage containers and a freezer with a constant temperature of 18 degrees Celsius . I replicated my experiment using the same experimental procedure and achieved the same results with a slight variation in the loss of volume in the hot sample, in my second attempt the hot sample lost 35% of its volume. Because I achieved resembling results using the same experimental design I believe my observations are valid.Works CitedJeng, M. (n.d.). Retrieved from http//math.ucr.edu/home/baez/physics/General/hot_water.htmlHistory Jeng, M. (2006). The Mpemba effect When can hot water freeze faster than cold? . American Journal of Physics, 514. Kurtus, R. (n.d.). Retrieved from http//www.school-for-champions.com/sci ence/mpemba.htm Osborne, E. M. (n.d.). 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