The formula for the volume of a sphere is
, where
is the radius of the sphere
The form for a spiral may be expressed as
), though an Archimedean spiral only occurs when
For distance of closest approach:
As the electric potential energy between an alpha particle and the nucleus of a gold atom is 0 when the alpha particle is at its starting position,
(
) will be at its maximum. However, as the alpha particle approaches the nucleus, it will be deflected, indicating
(
) will be at its maximum. Assuming energy is not lost, we can use the conservation of energy to establish that
, thereby implying that
. Rearranging this relationship for
will yield
, the distance of closest approach between the alpha particle and nucleus
Derivation for the volume of a cone
[edit]
We have established that the radius of the cone,
, and the height,
, form a right angle triangle with the cone's slant height. We can represent this in the form of a linear function (or straight line)
. If one were to treat the x-axis as the height and the y-axis as the radius, then they can represent said function as
. To obtain the volume of the cone's formula, we can rotate the function – from the function's x-intercept,
, to a value of
dictated by
– along the x-axis by
radians through solid of revolution and apply the volume of revolution formula
. This yields the following: