1. Some of the possible sources of error are incorrect reading of the dial gauge and digital multi tester as well as the improper plugging of the ohmmeter into banana plug which will alter the resistance reading. For these possible sources of error, one should read the dial gauge once it really stopped and make sure to set it at zero during the start of the experiment, read the tester after 30 seconds without changing and attach the ohmmeter into plug as much as possible.

2. The results will not be different even though the condensed water is not drained inside the expansion tube because the condensed water will just take the same temperature as that of the temperature inside the expansion tube making the readings still the same with or without the presence of the condensed water inside the tube.

3. From: Formulas We can say that a=a for 1-dimension, o=2a for 2 dimensions and B=3a for 3-dimensions.Therefore: Aluminum: Copper:

ANALYSIS

Based from the data results gathered in the experiment, I found out that when the resistance decreases the temperature increases and vice versa this is caused by the intermolecular forces of attraction between the molecules brought by the change in temperature.

Since heat is applied to metal tubes, we expect the metal tubes to expand linearly to a negative power. After computing, the change in length for aluminium is 1.05 mm and 0.81 mm for copper. It is because of the coefficient of linear expansion of both metals, the coefficient of aluminium is greater than that of the copper’s leading to a greater increase in aluminium.

To determine whether we’ve got reasonable values, we also computed for the percentage error of our computed coefficient of linear expansion and the actual values, after computing we arrived with 3.98 % and 5.08 % for aluminium and copper, respectively. Having small values of percentage error, we can say that our values are somewhat reliable.

CONCLUSION  In physics, thermal expansion is the tendency of any object to expand or contract upon experiencing a change in temperature. Based from the results of the experiment, an object will have a change in dimensions when the temperature is increased or decreased. An object expands linearly by how much its computed coefficient of linear expansion was, we can therefore conclude that both change in length and coefficient of

linear expansion was directly proportional to each other which is also seen in the

mathematical equation of α=∆ LLo∆ t , where α is the coefficient of linear expansion.

The first objective of the experiment was met since we are able to determine both the coefficient of linear expansion of Aluminum and Copper. Contrasting the two metals, we can theoretically conclude that aluminium will have greater change in length than that of the copper’s because it has greater coefficient of linear expansion, thus same thing follows with the change in length, since both are directly proportional.

The second objective of the experiment talks about the factors affecting the change in length in thermal expansion, after conducting the experiment we then conclude that those factors include:

- change in temperature- original length of the substance- nature of the substance- coefficient of linear expansion

First, change in temperature is the function in the change of the body’s dimension be it the linear dimension, area or even volume. Second, original length for it will be the basis of how much a substance will increase. Third, nature of the substance, but since we used two metals in the experiment then they have the same properties and therefore can be compared after such experiment. Lastly, the computed coefficient of linear expansion for it is directly proportional to the increase in length.