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Computer Intensive Physics 211Spring, 1998 InfoMall Homework #23 -Printed only (10 points) IFHW23
HOMEWORK

Due 4/9/98

In today's experiments you probably discovered that:
*when using similar amounts of water the final temperature was a middle point between
the initial temperatures of the samples.
*when the amounts of water were different the final temperature was weighed towards
the initial temperature of the more massive sample.
*the same rules do not seem to apply when using different materials, like the piece of
metal.
This homework will help you understand your results in a more quantitative manner.

*

When heat is added to a substance, its temperature usually rises. (An exception to this statement is when a substance undergoes a phase transition, say from a liquid to a gas, from solid to liquid, etc.) The quantity of heat required to raise the temperature of a given mass of a substance varies from one substance to another.

(1)Search the InfoMalland find definitions for Heat Capacityand Specific Heat. Find the specific heats of common substances, like water, copper and aluminum.

*

The quantity of heat required to raise the temperature of a given mass of a substance is related to its specific heat by:

Q=mcDT=mc(T_f-T_i),

where m is the mass, c is the specific heat, and T_fand T_iare the final and initial temperatures of the substance. Using this, and knowing the law of conservation of energy for heat, we can explicitly determine formulas for the final temperature of a mixture. Below in an example calculation showing the way to determine the formula for the experiment where similar amounts of water were used.

IMAGE imgs/IFHW2301.gif

(2)Determine formulas for T
of water are different, and when the mixture is made of different substances.^f^{for the other two parts of the experiment: when the amounts}



Computer Intensive Physics 211Spring, 1998 InfoMall Homework #23 -Printed only (10 points) IFHW23 HOMEWORK
			Due 4/9/98
In today's experiments you probably discovered that: when using similar amounts of water the final temperature was a middle point between the initial temperatures of the samples. when the amounts of water were different the final temperature was weighed towards the initial temperature of the more massive sample. *the same rules do not seem to apply when using different materials, like the piece of metal. This homework will help you understand your results in a more quantitative manner.
*
	When heat is added to a substance, its temperature usually rises. (An exception to this statement is when a substance undergoes a phase transition, say from a liquid to a gas, from solid to liquid, etc.) The quantity of heat required to raise the temperature of a given mass of a substance varies from one substance to another.
(1)Search the InfoMalland find definitions for Heat Capacityand Specific Heat. Find the specific heats of common substances, like water, copper and aluminum.
*
	The quantity of heat required to raise the temperature of a given mass of a substance is related to its specific heat by:
		Q=mcDT=mc(T_f-T_i),
where m is the mass, c is the specific heat, and T_fand T_iare the final and initial temperatures of the substance. Using this, and knowing the law of conservation of energy for heat, we can explicitly determine formulas for the final temperature of a mixture. Below in an example calculation showing the way to determine the formula for the experiment where similar amounts of water were used.

(2)Determine formulas for T of water are different, and when the mixture is made of different substances.^f^{for the other two parts of the experiment: when the amounts}