Re: [Phys-l] Interactive Physics Question

[John Denker <jsd@av8n.com>]

On 10/18/2007 09:56 AM, Ron Curtin wrote:
>  A physical example would be a "relay" race
> situation when one runner starts moving at almost constant speed when the
> other runner reaches a certain point in the race.  


Actually, there's a physics lesson in that.

It would be _unphysical_ for the second runner to discontinuously
change velocity.

In fact the standard procedure for relay races is for the second
runner to anticipate the handoff and be up to speed before 
reaching the handoff zone.

The amount of anticipation is usually quantified as a distance.
  http://en.wikipedia.org/wiki/Relay_race
It is a nice elementary homework problem to calculate the
required distance, based on speed and acceleration ... or work 
conversely to find acceleration based on speed and distance.