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Re: Name that force


Ludwik Kowalski wrote:

>In a conceptual question Hewitt asked what
>happens to the speed of an open freight car
>(increases, decreases or remains the same)
>when it rolls friction-free along a horizontal
>track while a pouring rain falls vertically.
>
>The expected answer is: "speed decreases
>as water accumulates in the car because the
>momentum must be conserved." What is a
>good name for a force responsible for the
>change in speed?
>Ludwik Kowalski
>
>


In a flat bed, a contributor would be the Fanning force:
viscosity per kinetic energy, don't you think?



Brian Whatcott Altus OK Eureka!