Question

State the properties of the line that would indicate that f is directly proportional to d in physics

Answer 1

proportional if there is always a constant ratio between them. The constant is called the coefficient of proportionality or proportionality constant.

If one variable is always the product of the other variable and a constant, the two are said to be directly proportional. x and y are directly proportional if the ratio
y
/
x
is constant.
If the product of the two variables is always a constant, the two are said to be inversely proportional. x and y are inversely proportional if the product xy is constant.
To express the statement "y is directly proportional to x" mathematically, we write an equation y = cx, where c is the proportionality constant. Symbolically, this is written as y ∝ x.

To express the statement "y is inversely proportional to x" mathematically, we write an equation y =
c
/
x
. We can equivalently write "y is directly proportional to
1
/
x
".