proportion
Two variables, X and Y, are said to be in direct proportion if X/Y is a constant. Equivalently, Y = cX for some constant c.
It is the constant of proportionality.
Weber's Law"Ernst Weber noted that for people to really perceive a difference, the stimuli must differ by a constant "proportion" not a constant "amount."
Joseph Proust.
proportion
Two variables, X and Y, are said to be in direct proportion if X/Y is a constant. Equivalently, Y = cX for some constant c.
It is the constant of proportionality.
The state of being in proportion.
Having a due proportion, or comparative relation; being in suitable proportion or degree; as, the parts of an edifice are proportional., Relating to, or securing, proportion., Constituting a proportion; having the same, or a constant, ratio; as, proportional quantities; momentum is proportional to quantity of matter., Any number or quantity in a proportion; as, a mean proportional., The combining weight or equivalent of an element.
x and y are in direct proportion if there is some positive constant c such that y = cx
Weber's Law"Ernst Weber noted that for people to really perceive a difference, the stimuli must differ by a constant "proportion" not a constant "amount."
Joseph Proust.
The Circumference of a circle is directly proportional to the diameter. The constant of proportion is 'pi = 3.141592....'. Another one is force is directly proportional to mass. The constyant of proportion is acceleration.
proportion beriod
Pi is a constant because it is the ratio of the circumference to the diameter of a circle and they are always in the exact same proportion.
This was an idea of John Dalton.