I have a question:
I have an elastic band. I start to 'whirl' it around my head like a lasso. As i whirl it, the circle that the band is traveling on (it's arc i guess) gets bigger and bigger as i whirl the band faster.
how is that happening?
Jim,
If I really could explain the exact nature of inertia force I would be a sure candidate for the Nobel Prize in Physics. I would than likely also be capable of explaining that mysterious gravity force as well. As so often science looks at things, describes but not necessarily explains.
It is indeed bizarre the way inertial forces remain a mucky and conflictual subject in science. During Newton’s time it was indeed a very hard struggle to come very slowly over time to grasp with the concepts of mass, force, momentum, inertia. Yet another 300 yeas later it is not all that much different.
For instance, inertial forces, during Stalin’s reign were condemned to be wrong concepts and scientists not treating them according to the official party science were considered ideological enemies and some were indeed persecuted.
Jim, let’s just forget about all this mucky conflictual information. Just between the two of us we are going to see what we can make of this mysterious inertial force, of which centrifugal force is one specific manifestation.
The inherent nature of inertial forces is that they last only as long as there is some motion. A car stuck in heavy snow has no inertial force. However it will resist stubbornly when trying to set it into motion. A golf ball will only exert an inertial force when crushing the skull of a poor spectator as long as it has motion.
Earthquakes, tornadoes, tsunami waves, typhoons, are all capable of producing huge damage solely due to having massive amount of motion. A tsunami wave once it finds an obstacle in its way becomes a darned vicious and mortal destructive inertial force. Yet to make things mucky as usual text books frequently refer to them as fictitious forces, not making the necessary and required distinction about reference frames.
Back to the business of our poor little golf ball, hopefully enjoying himself at the end of your elastic band. The golf ball is in motion so we are from our reasoning above also expecting a manifestation of some form of inertial force.
Let’s do it the homocentric way. The golf ball like human beings is basically inert, lazy and hates to be forcefully set into motion. It likes to get away from that annoying irritating piece of elastic pulling him constantly towards a center. It resists valiantly with its secret weapon, its inertial force.
The elastic band wants to impose itself and without any pity or regard for the feelings of the golf ball keeps pulling hard to keep that damned stubborn golf ball towards the center.
Since nature usually likes to balance things the struggle ends up in a perfect draw. As hard as the elastic band is pulling in as hard is the ball fleeing away from that center. It is like a rat race, like a snake frantically trying to bite its tale and yet just can’t manage it.
The harder the elastic band pulls on the ball the more the ball resists with its inertial force. A larger force means that the elastic band needs to stretch a bit, allowing the ball a bit more space away from the center.
Don’t get mistaken on the apparent very peaceful appearance of the circular motion. It is in effect concealing a fierce continuous battle going on between a center seeking force (centripetal) and a center fleeing force (centrifugal) keeping a continuous dynamic yin and yang type balance.
Jim, in a nutshell, we really don't know how to explain the intrinsic nature of inertial force. Let's just simply accept that it is there. It is indeed very real in its multiple manisfestations. If I find an explanation I am afraid that I will not post it on this forum -a potential Nobel Prize idea merits a different type of forum.
