Instant Centers Understood Not Instantaneous

Four Hundred Ninth Post: Instant Centers Understood Not Instantaneous (20090106)

Well it has taken me almost 10 years from college, but I think I finally understand instant centers of rotation and relative velocity. That is “I think I understand”.

Back when I was in school I had a class in dynamics. Everything was pretty basic and crossed over from physics, but when we started doing the relative velocity I was confused. Of course it didn’t help much that I missed 2 weeks of class.

But now I followed the example of “Engineering Mechanics: Dynamics” 5th edition, Meriam, Kraige and have followed the examples and understand. It is important to note this book is not rated high on Amazon, mostly because of its difficulty. But I believe it is an excellent text filled with great problems.

The reason I never understood the relative velocity is because I couldn’t find which forces to sum and where to start. The angular velocity equations are pretty much clear, but if you don’t understand the forces you cannot solve the problem because you cannot simply “plug and chug”. And it is how you set up the problem. A dynamics problem usually takes 5 to 20 min to solve. It is too easy to get lost in you work. And you start to worry when your taken a test that only has 2 or 3 problems on it.

But that is the past. I’m am looking to the future when I can solve one these problems and show you my approach and technique. As with any problem on Constructors Corner there is a high chance that I will be wrong. However I think I can show this problem and demonstrate why I used to not be able to solve them.

Look for it soon. It is about time I stopped playing with that darn log spiral.