The fundamental units together with all the derived units from
Answers
Explanation:
The fundamental units of greatest interest in mechanics are meters, seconds, and kilograms. From these three all of the other units of mechanics can be derived. The long held and historical practice for defining units is that they must be expressed as a combination of previously existing units. Fundamental or base units are units that cannot be expressed as a combination of previously existing units. They are naturally indefinable. There are two naturally indefinable units. They are meter and second. These are the units in which empirical evidence is expressed. There are no units that pre-exist meter and second.
The units of meter for length and second for ‘time’ are undefined as are their associated properties of length and ‘time’. The units of meter and second are both based upon arbitrary rules of measurement offcially agreed upon for common use.
The first error of theoretical physics was the decision to accept mass as the third indefinable property of mechanics. The three indefinable properties are: Mass; Length; and, what physicists call the property of ‘time’. Both length and physics’ ‘time’ are naturally indefinable properties. Mass could have been and should have been formally defined at the time that it was introduced to us by direct empirical evidence.
However, it remains not understood how to formally define mass and its unit of the kilogram. A formally defined property and a formally defined unit are defined by an equation that expresses them in terms of other properties or, in the case of the kilogram, in terms of other units.
The strict historical method for formal definitions includes the requirement that a defined property must have an equation where the defined property is expressed in terms of other properties that have been previously introduced to us by direct empirical evidence. Length and ‘time’ are naturally formally indefinable because there are no properties previously introduced to us in terms of which they might have been definable.
The first two properties that are formally definable are force and mass. Force can be defined, i.e., force is automatically defined by the equation f=ma, but force represents cause. All physics knowledge consists of effects only. we learn what cause does but not what cause is. The formal physics definition for force cannot tell us what is cause,
Mass is the only property that is introduced to us directly by empirical evidence that is formally definable. The problem that theoretical physics has never solved is: How can mass be defined in terms of the only two properties previously introduced to us, i.e., length and ‘time’? This could have been done and should have been done at the time that mass was first introduced to us in the equation f=ma.
This step cannot be avoided because the cost to do so is the removal of mass as the first and only link between direct empirical evidence and all of the rest of physics. Whatever it is that direct empirical evidence is attempting to teach us about the property of mass, is lost. For all of the rest of physics that follows, the common cost is the immediate loss of fundamental unity from all physics equations that include dependency upon mass.
In answer to your question: examples of fundamental units are: Joule; Newton; Kilogram; Meter; and, Second. From this list, examples of derived units are: Joule and Newton. Only formally defined units are derived units. The Joule is defined as Joule=Newton x meter. The Newton is defined as Newton=kilogram x (meter/second/second).