Parallel axis theorem and moment of inertia

[Edwardo_Elric]

Homework Statement

A thin rectangular sheet of steel is 0.30m by 0.40m and has mass 0.470kg. Find the moment of inertia about an axis that is perpendicular to the plane of the sheet and that passes through one corner of the sheet.

Homework Equations

Parallel axis theorem:
Ip = Icm + Md^2
Rectangular plate(but not thin):
Icm = 1/12 M(a^2 + b^2) << where a and b are the sides of the rectangle

The Attempt at a Solution

Ip = 1/12((0.30)^2 + (0.40m)^2) + (0.470kg)((0.15m)^2 + (0.20m)^2)
Ip = (0.0208333 + 0.029375)kg * m^2
Ip = 0.05021 kg * m^2

 

[learningphysics]

Homework Statement

A thin rectangular sheet of steel is 0.30m by 0.40m and has mass 0.470kg. Find the moment of inertia about an axis that is perpendicular to the plane of the sheet and that passes through one corner of the sheet.

Homework Equations

Parallel axis theorem:
Ip = Icm + Md^2
Rectangular plate(but not thin):
Icm = 1/12 M(a^2 + b^2) << where a and b are the sides of the rectangle

The Attempt at a Solution

Ip = 1/12((0.30)^2 + (0.40m)^2) + (0.470kg)((0.15m)^2 + (0.20m)^2)

you didn't multiply by M... 1/12M (a^2 + b^2)