Here's why:
* Direct Comparison: A balance scale allows you to place the rock on one side and the two wooden blocks on the other side. This directly compares the gravitational forces acting on each object, giving you a clear indication of which side is heavier.
* Accuracy: Good balance scales are highly sensitive and can provide accurate readings, even for relatively small differences in mass.
* Simplicity: Balance scales are simple to use and don't require complex calculations.
Other Tools (less ideal):
* Spring Scale: A spring scale measures weight (force of gravity on an object), which is proportional to mass. However, it might not be accurate for very heavy objects, and its accuracy can vary depending on the spring's condition.
* Digital Scale: A digital scale provides a numerical reading of the mass. However, it may have limitations on the maximum weight it can handle.
* Volume Measurement: If you know the density of the rock and the wood, you can calculate their mass from their volumes. However, this requires accurate volume measurements and knowledge of the materials' densities.
Important Note: Make sure the balance scale is properly calibrated before use.
