Question

What is the concept of proportionality?

Answer 1

a:b = c:d [ two ratios are equal then a,b,c,d are called in proportion

Answer 2

For further explanations, would you please do a quick Internet search for "proportionality."

Answer 3

Proportionality can be defined as the quotient of any two magnitudes are equal to a constant "k" whiwh is called the "constant of proportionality":
\[\vec v =k.\vec u \]
Thereby:
\[\frac{ \left| \left| \vec v \right| \right| }{ \left| \left| \vec u \right| \right| }=k\]
This means that the vectors U and V are collinear and since colinearity is a relation of proportion it means that their modules are proportional.

Answer 4

all it is in word terms is basically this:
you have one thing and it equals another because they are "proportionate" hence: \[concept of proportionality\]

Answer 5

\[y\propto x\\\implies y=\alpha x\qquad\alpha\in\mathbb R\]