The densities of all three objects were successfully determined. The density of the padlock was 6.0 g/cm 3, and the density of the rock was 2.63 g/cm 3. Both of these values seem quite reasonable, since both of these objects sink in water, which has a density of 1.0 g/cm 3, and the padlock seems relatively heavier for its size than the rock. The density of the wooden block was found to be 0.85 g/cm 3 using the volume measured by displacement, and 1.06 g/cm 3 using the volume determined by formula. Since the block readily floats in water, the former value appears to more reliable, since it is less than one. The volume determined by the formula method was probably in error, since the block was not a box shape which the formula requires. This may have resulted in an under estimation of the blocks volume. Several problems with the equipment may have introduced error into the measurements. Firstly, the 500 mL graduated cylinder was only marked in 10 mL increments, requiring estimation for levels in between. Secondly, use of the overflow tank required the transfer of water twice, possibly causing a loss of liquid and a lower than true volume. This problem could be solved by letting the overflow water go directly into the graduated cylinder. Thirdly, the volume of the wooden block was measured by displacement first, then by formula~ The block swelled slightly after wetting, possibly increasing its dimensions and consequently the calculated volume. The error introduced by these problems was slight, however, and the calculated densities for the three objects are probably quite reliable.
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