Four particles, one at each of the four corners of a square with 2.5-m-long edges, are connected by mass less rods. The masses of the particles are m1 = m3 = 2.0 kg and m2 = m4 = 7.0 kg. Find the moment of inertia of the system about the z axis.
Well, to find the moment of inertia of the system about the z axis, we can think of the square as a spinning circus act. Picture those particles as clowns on unicycles!
Now, let's calculate the moment of inertia. Since the rods are mass-less, we only need to consider the masses of the particles. Let's label the corners of the square as A, B, C, and D, with A being the bottom left corner and going clockwise.
To calculate the moment of inertia, we need to consider the distance from each particle to the z-axis and square it, then multiply it by the mass of that particle: