That’s true. And only some of those things can be computed, and some are inexact. But I’m surprised that some people voted for ‘fake’ on every item except for the center of mass (only one vote for ‘fake’).
A while has passed since the poll, so I guess we can discus this now:
Food calories: the energy that human metabolism can free from a food. 1 food calorie = 4200 J. The definition is precise, and can be measured exactly with a calorimeter.
Digestion and metabolism can deviate from that definition. Wikipedia notes that “alterations in the structure of the material consumed can cause modifications in the amount of energy that can be derived from the food; i.e. caloric value depends on the surface area and volume of a food.” People also have individual metabolic differences. Still, it’s a useful unit of measure.
The position of an object’s centre of mass has a strict definition. To calculate it you need to know the distribution of mass in an object, but you do know it for many objects.
The population mean is defined by Wikipedia as equal to the arithmetic mean over the whole population—for a finite population. That seems simple enough that I’m confused that some people voted it was ‘false’.
The population mean is defined by Wikipedia as equal to the arithmetic mean over the whole population—for a finite population. That seems simple enough that I’m confused that some people voted it was ‘false’.
It can be a fake number if we have no practical way to survey every member of the population.
That’s true. And only some of those things can be computed, and some are inexact. But I’m surprised that some people voted for ‘fake’ on every item except for the center of mass (only one vote for ‘fake’).
A while has passed since the poll, so I guess we can discus this now:
Food calories: the energy that human metabolism can free from a food. 1 food calorie = 4200 J. The definition is precise, and can be measured exactly with a calorimeter.
Digestion and metabolism can deviate from that definition. Wikipedia notes that “alterations in the structure of the material consumed can cause modifications in the amount of energy that can be derived from the food; i.e. caloric value depends on the surface area and volume of a food.” People also have individual metabolic differences. Still, it’s a useful unit of measure.
The position of an object’s centre of mass has a strict definition. To calculate it you need to know the distribution of mass in an object, but you do know it for many objects.
The population mean is defined by Wikipedia as equal to the arithmetic mean over the whole population—for a finite population. That seems simple enough that I’m confused that some people voted it was ‘false’.
It can be a fake number if we have no practical way to survey every member of the population.