Based on the data I collected, the ruler with the smaller divisions gave me more precise measurements of volume. The method of measuring the volume of the rubber ball using the displacement of water was more accurate, as it closely matched the theoretical value. However, the method using the ruler was more precise, as it consistently provided measurements with smaller variations.
The accuracies of the volume and density calculations did depend on the precisions of the instruments used. The more precise ruler allowed for more accurate measurements of volume, which in turn affected the accuracy of the density calculations.
In terms of time measurements, the stopwatch method was more precise than using the sensors. The stopwatch consistently provided more consistent and repeatable measurements, whereas the sensor measurements had larger variations.
Factors that might have contributed to the uncertainty of time measurements when using the stopwatch could include human reaction time, inconsistencies in starting and stopping the stopwatch, and potential errors in reading the time from the stopwatch.