RealWorld

 I wondered how the rolling wheels connected to the carbody that is parallel to the ground.  I could have guessed that cogs and bearings would be in between. But can they withstand that enormous weight? I was curious about the detailed structure. So I decided to find out. Drive shaft, Differential, Suspension, Wagon wheel ..  In the process of learning, I learned various interesting concepts. But I haven't found anything I'm really curious about.  However, while watching a video explaining how the engine works, the concept of how to change the rotation into a linear force emerged. I thought this is it. Then I got to know the bearing and found the real answer. Bearings are mechanical elements that reduce friction between moving objects. In short, several small balls play a role in transmitting one turn to the other. *Tribology : the science of wear, friction and lubrication, and encompasses how interacting surfaces and other tribo-elements behave in...