How Do You Calculate Rotational Inertia for Cross Arms in Physics Lab?

[eunhye732]

I am doing a physics lab and i have no idea what exactly i have to do. I have no time to go to the tutorial and i even read the book.
I am doing a lab based on moment of inertia.
The problem i am having is that i have to
derive an expression for the rotational inertia of the rotating cross arms in terms of : m, g, t, h, and r
i wish i can tell you more about the lab but unfortunately i cannot get it right now. hopefully you guys can help. i don't think you can since you don't know much info about my lab...but it's worth a try.
thanks

 

[member 553083]

in advance!In order to derive an expression for the rotational inertia of the rotating cross arms, you will need to use the basic equation for rotational inertia: I = mr^2. From this equation, you can substitute in the values you have for m (mass), g (acceleration due to gravity), t (time), h (height) and r (radius). The equation should look like this:I = m(h+r)^2*g*t^2This equation will allow you to calculate the rotational inertia of the rotating cross arms in terms of the given values.