Re: Car acceleration

[Jack Uretsky <jlu@HEP.ANL.GOV>]

        Cute.  And, of course, valid.
                                Jack

On Mon, 4 Feb 2002, Scott Goelzer wrote:

> Is this a valid demo?
>
> Take a toy pull-back car. Pull it back and let it go. Ask what made it go?
> Student responses vary (usually the spring made it go) but seldom mention
> the table. Pull back the car, lock the drive wheels with fingers, release
> the car over the table in the air. Much spinning and noise, but no forward
> motion until contact with the table.
>
> The table provides the forward force that makes the car go.
>
> Place a file folder on a bed of straws so that it slides freely. Place
> wound-up car on file folder and release. Car pushes road backwards.
>
> I've been using this for years as a third law/friction demo.
>
>
>
> *****************************
> S.Goelzer
> Physics Teacher
> Coe - Brown Northwood Academy
> Northwood NH 03261
> 603-942-5531 ext43
> sgoelzer@coebrownacademy.com
> *****************************

--
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It is your strength against my intelligence.  It is a veritable potpourri
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                     <The 5-MINUTE ILIAD and Other Classics>