Homework Help

What is the moment of inertia about an axis through A?Three particles are placed at the...

user profile pic

greg1234 | Student, Grade 9 | (Level 3) eNoter

Posted November 28, 2010 at 2:24 AM via web

dislike 0 like

What is the moment of inertia about an axis through A?

Three particles are placed at the vertices of a triangle ABC. The particles weigh .3 kg, 0.1 kg and 0.2 kg respectively. The length of the sides AB, BC and CA are 0.5m, 0.3m and 0.4m resp.

 

1 Answer | Add Yours

Top Answer

user profile pic

justaguide | College Teacher | (Level 2) Distinguished Educator

Posted November 28, 2010 at 2:27 AM (Answer #1)

dislike 1 like

The moment of inertia is the sum of the products of the mass of the bodies with the square of the distant from the axis. When the moment of inertia is being found about an axis through A, we need the following values:

Distance between A and B is 0.5 m and the mass of body at B is 0.1 kg

Distance between A and C is 0.4 m and the mass of body at C is 0.2 kg

To calculate the required moment of inertia, we need to add 0.1*0.5^2 and 0.2*0.4^2. This is equal to .025 + .032 = .057 kg*m^2.

The required moment of inertia is .057 kg*m^2

Join to answer this question

Join a community of thousands of dedicated teachers and students.

Join eNotes