Question

1. Explain in which cases the mass determination method is used:

(a) through the interaction of bodies

(b) by means of the balance.

2. What does it mean that the mass of a body has the additive property?

Answer 1

1. Mass measurements in sciences are performed using a balance. There are different types of scales and balances, but two methods can be used on most instruments to measure mass: subtraction and taring.

• A balance or scale is an instrument used to measure mass in the science laboratory.
• One common method of measuring mass is to tare the scale and measure the mass directly. For example, this is how people weigh themselves.
• The other common method is to place a sample into a container and measure the mass of the container plus sample. The mass of the sample is obtained by subtracting the mass of the container.

  Direct Weighing:

Direct weighing means that an object is placed directly on a balance and the mass read. Weighing directly requires that the balance be carefully zeroed (reads zero with nothing on the balance pan) in order to obtain accurate results.

2. That mass is additive is an empirical fact which we use without question in constructing our physical and mathematical models of the universe. We could imagine that if the universe had different Laws Of Nature then bringing two bodies together might increase their combined mass above the sum of their separate masses, just as bringing two charges together increases the force between them.

An ultimate Theory of Everything might "explain" this property in terms of some abstract concepts, but this will only "prove" that that theory is consistent with our observations.