Weber's Law
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."
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.
x and y are in direct proportion if there is some positive constant c such that y = cx
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.
Yes, that's correct. Weber's law states that the just noticeable difference (JND) between two stimuli is proportional to the intensity of the initial stimulus. This means that the difference needed to perceive a change in stimulus intensity remains constant regardless of the initial intensity level.
If two variables are in direct relationship then the ratio of the two variables is known as the constant of proportion between them. In algebraic form, if X and Y are the two variables, then direct proportionality implies that Y = cX and c is the constant of proportionality.
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.