hi all, This is a question regarding calculation of effort required to over come the inertia of a body.Let us have a ring(Some random example) which is supported by three rollers(Ring is sitting on the rollers).To rotate the ring,the applied effort has to overcome the friction and inertia of the body.The frictional force can be calculated using the coefficient of friction for line contact and the normal reaction (Weight of the body).But to calculate the force to overcome inertia mass of the body and the acceleration of the body has to be considered.This "acceleration " part that is quiet confusing to me. How can I calculate the acceleration if I Manually push the ring.For example,I know how much distance I have to push(The circumference if I make one complete rotation),The time for rotation and that the initial velocity is zero(For first rotation).Can I use Equations of motion ( s=ut+0.5at^2) to find the acceleration which I can use in the Calculation of Inertial force?. If I am too confusing,Simply put I want to know how to calculate the force required to overcome the inertia of a body If i know mass,distance to travel,time and initial velocity. I am just trying to understand the concept so don't mistake me if i have misstated something. Sorry for attaching a crappy image.I am on summer vacation and I only have paint installed in this computer(Even with paint many can do better but I can't) Thanks in advance.