The Speed of Change: Centripetal Force

AI Thread Summary
The discussion centers on the concept of the speed of change in relation to centripetal force, particularly how changes in the position of a central body affect a rotating body. It highlights that all fields, including gravitational, propagate at the speed of light (c), meaning that if a central body like the Sun were to explode, the effects would not be felt by a rotating body like Earth for about eight minutes. The conversation also touches on the distinction between linear acceleration and more complex changes in speed, referred to as 'jerk,' which are relevant in fields like roller coaster design. Theoretical considerations are raised regarding the existence of a speed limit (c) for these changes, questioning why instantaneous communication of changes isn't possible. Overall, the discussion explores the implications of speed limits in physical systems and their effects on motion.
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I was just thinking that whether changes have any speed.
Suppose we have a system in which a bodyA is rotating around an other body B through centripetal force. If B gets an instantaneous hit so that its position changes. Then what will be the speed of change or effect or whatever with which the displacement of B is communicated to A:confused:
 
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The speed is c.

All electric, magnetic, and gravitational fields move at c.
 
Which translates into: If B were the Sun and it suddenly exploded at this very moment, and A were the Earth, then we wouldn’t experience any gravitational effects for another 8 minutes.
 
Sure the speed of change can change. In classical physics, the speed of change is called acceleration - a first order [linear] change in speed v time. But the rate of change need not be linear, nor is it unphysical - in roller coaster design it is routine to consider second order changes in the speed of the speed of change. The technical term for this is 'jerk'. In geometry this can be compared to the difference between the area of a circle and volume of a sphere.
 
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Chronos, I'm really surprised that such a thing like speed of change existed theoretically. But, why is there a limit (c) to this speed. Can't it be instantaneous.
 

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