A change in temperature may cause various changes in physical properties of an object due to the response of its particles. One of those changes is the volume of object. Typically, when an object is heated, its particles receive energy, increase the frequency and magnitude of their motion, and as a result, increase collisions and volume of object. Conversely, when an object is cooled, its particles decrease motion activities, decrease collisions, and the object shrinks. This tendency of matter is called thermal expansion.
Coefficient of expansion is thermal property of matter. The coefficient of linear expansion (α) is defined as “ratio of fractional change in length to the change in temperature” (Tipler, 666). This coefficient only applied for solids.
ΔL/L 1 dL α = lim =
ΔT→ 0 ΔT L dT
The coefficient of volume expansion (β) is defined as “ratio of fractional change in volume to the change in temperature, at constant pressure.” β = 3α
Commonly, gases and liquids have higher coefficient of volume expansion. Materials with higher coefficient of expansion subjects to larger change in length or volume, and as a result, more likely to crack during rapid heating or cooling processes. When two materials with great difference of coefficients of expansion combine, cracking or separation may occur at the binding surface due to different thermal expansion rates.
In industries and everyday life, thermal expansion has many important positive and negative consequences. One of the most important consequences of thermal expansion is in the construction of large structures, such as bridges, buildings, railway tracks, s...
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...logy 4. Geological Society. pp. 129–164. ISBN 1-86239-249-8.
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Holand, Wolfram; Beall, George H.. Glass Ceramic Technology (2nd Edition).
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Lerner, Ed. K. Lee and Brenda Wilmoth Lerner. "Bridge expansion joint." The Gale Encyclopedia of Science. 4th ed. Detroit: Gale, 2010. Science in Context. Web. 26 Nov. 2013.
Tipler, Paul Allen, and Gene Mosca. "Temperature and Kinetic Theory of Gases." Physics for Scientists and Engineers. New York: W.H. Freeman, 2008. 566-670. Print.
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The purpose of the lab is to understand how to calculate the calorimeter constant by using a calorimeter. This allows us to analyze the heat reaction of different substances. Calorimetry is a word that comes from both Latin and Greek. The prefix “Calor” in Latin signifies heat and the suffix “metry” in Greek means measuring. Therefore the word itself translates to measuring heat. Joseph Black, was the first scientist to recognize the difference between heat and temperature. Energy is always present in chemical and physical changes. The change of energy that occurs when there is a chemical change at constant pressure is called enthalpy. Enthalpy changes , as well as physical and chemical changes, can be measured by a calorimeter. The energy that is released or absorbed by the reaction can be either absorbed or released by the insulating walls of the instrument.
When there is a heat exchange between two objects, the object’s temperature will change. The rate at which this change will occur happens according to Newton’s Law of heating and cooling. This law states the rate of temperature change is directly proportional between the two objects. The data in this lab will exhibit that an object will stay in a state of temperature equilibrium, unless the object comes in contact with another object of a different temperature. Newton’s Law of Heat and Cooling can be understood by using this formula:
on how long it takes to heat up. If we heat a large volume of water it
A hot plate is acquired and plugged in and if left to warm up. Fill two beakers with 0.075kg of water and record the temperature using a thermometer and record it. Place one of the beakers onto the hot plate and drop one of the metal objects in. Wait for the water to boil and wait two minutes. Take the object out of the water and drop it into the other beaker. Take the temperature of the beaker and record the rise in temperature.
The molar specific heats of most solids at room temperature and above are nearly constant, in agreement with the Law of Dulong and Petit. At lower temperatures the specific heats drop as quantum processes become significant. The Einstein-Debye model of specific heat describes the low temperature behavior.
As the temperature increases, the movements of molecules also increase. This is the kinetic theory. When the temperature is increased the particles gain more energy and therefore move around faster. This gives the particles more of a chance with other particles and with more force.
What Is The Effect Of Various Temperatures On Milk Fat Mass From Shaken Heavy Cream?
Cengel, Y. A., & Boles, M. A. (2011). Thermodynamics: An engineering approach (7th ed.). New York, NY: McGraw-Hill.¬¬¬¬
Hypothesis: As the ratio of surface area to volume of an object decreases the rate of heat loss from the object will also decrease. Objects with the same surface area to volume ratios loose heat at the same rate so long as there are not other variables involved.
Heat is thermal energy being transferred from one place to another, because of temperature changes. This can take place by three processes. These three processes are known as conduction, convection, and radiation.
As the pressure drop increases in the column, it is observed that the degree of foaming becomes more violent and more spread out. When the pressure drop is relatively high, it means that the pressure exerted by the vapour is insufficient to hold up the liquid in the tray, causing the gas bubbles to appear on top of the sieve trays. To add on, the higher the pressure drop, the higher the velocity of the vapour passing up the column. As a result, more vapour will penetrate the liquid and more bubbles formation is observed. Due to more bubbles formation, the degree of foaming are more agitated, rapid and spread out.
As discussed in class, submission of your solutions to this exam will indicate that you have not communicated with others concerning this exam. You may use reference texts and other information at your disposal. Do all problems separately on clean white standard 8.5” X 11” photocopier paper (no notebook paper or scratch paper). Write on only one side of the paper (I don’t do double sided). Staple the entire solution set in the upper left hand corner (no binders or clips). Don’t turn in pages where you have scratched out or erased excessively, re-write the pages cleanly and neatly. All problems are equally weighted. Assume we are working with “normal” pressures and temperatures with ideal gases unless noted otherwise. Make sure you list all assumptions that you use (symmetry, isotropy, binomial expansion, etc.).
The rate of gasification is dependent on the total pressure, temperature, and partial pressure of gasifying agents.
H. Young, & R. Geller, Sears & Zemansky's College Physics, 8th ed., (Pearson Education Inc., San Francisco, 2007), pp. 422-426, 428, 430-431.