\varproptoThe \varpropto symbol is used to denote proportionality between two quantities. It indicates that one quantity is proportional to another, meaning that they change at the same rate or ratio.
y is proportional to x, meaning y = kx for some constant k.
y \varpropto xForce F is proportional to mass m, implying F = km for some constant k.
F \varpropto mArea A is proportional to the square of the radius r, indicating A = kr^2 for some constant k.
A \varpropto r^2