Help with moment of inertia problem

[iNCREDiBLE]

Hello!

I have a problem and I was kind of hoping that someone could help me out.

 

[whozum]

Give us some of your thoughts.

 

[iNCREDiBLE]

Give us some of your thoughts.

Well I I don't know where to start and what formula to use. As far as I can tell the area is 6x3 = 18 sq ft.

 

[HallsofIvy]

Okay, here are some hints: What is the DEFINITION of "moment of inertia"? What formulas do you know relating to moment of inertia?

 

[jackson]

u should actually try and understnd the definition of moment inertia before attempting the question. as u know the I, moment of inertia is affected by the shape of the solid and also at what point it is being referred to, so i had reckon u to understand the definition b4 attempting it.

 

[iNCREDiBLE]

The understanding tends to come afterwards (for me). The surface = one rectangel + two triangles... For the rectangle I = 4*3^3/12 = 9. The two triangles I = 2(2*3^3/12) = 9. So my answer is 18 ft^4. But is this a correct solution?

 

[iNCREDiBLE]

Please, can somebody help me & explain it to me...

 

[arildno]

Could you make a more thourough post on how you got those "answers".
And please, do not use numbers, but symbols.
That makes it easier for us to spot where you've made any mistakes.

 

[Pyrrhus]

Are you familiar with Steiner's Theorem or Parallel axis Theorem?