# Math Help - moment of area.

1. ## moment of area.

A circle has a radius of 0.4m. Determine its second moment of area
(ii)about an axis 1.8m from its centre of area.

2. Do you mean moment of inertia as that would make more sense but I can't be sure here is the way for moment of inertia

Moment of Inertia of a circle about its centre is
$
ma^2/2
$

and once the axis has been moved you can use the paralell axis theoreom and just add
$md^2$
Where d is the distance of the pivot from centre of mass of the object

so for part b you get
$ma^2/2 + md^2$