Phys 111L
Fall 2007
Laboratory 11: Heat Transfer
When heat is added to or removed from an object at constant volume or pressure, a
change in temperature results. The relationship between the magnitude of the heat Q
and the corresponding change in temperature depends on the object and is given by
Q=mc∆T(1)
where mis the mass of the object and cits specific heat.
In this experiment, you will investigate this relationship for various materials.
1 Experiment: Water at different temperatures
In this part of the experiment, you will mix two cups of water initially at different
temperatures and determine the heat which is transferred.
a) Start DataStudio and connect the temperature sensor. Display the temperature in
a graph and a digits windows.
b) Fill one cup less than halfway with water at room temperature. Determine the
mass of the water in the cup.
c) Fill another cup less than halfway with hot water. It will be important that the
water from both cups can be entirely accommodated in just one of the
cups. Determine the mass of the water in the cup.
d) Measure the temperature of the water in each cup. Ensure that the thermometer
does not touch the sides of the cup and stir the water while you measure.
e) Pour all of the water from one cup into the other and observe the temperature.
Measure the equilibrium temperature of the mixed water.
f) Determine the heat lost by the warmer water.
g) Determine the heat gained by the cooler water.
h) Determine the p ercentage difference between the heat lost by the warmer water
and that gained by the cooler water.
2 Experiment: Sp ecific heats of metals
In this experiment you will determine the specific heats of aluminum and copper.
The metal can be heated by immersing it in hot water, waiting for it to reach equilibrium
and then measuring the water temperature. Subsequently the metal can be immersed
in cool water, allowing for a heat transfer from the metal to the water.
a) Determine the mass of the aluminum.
