# Stuff that only sort of amazes me. **URL:** \ **Category:** Miscellaneous and Personal Stuff I Must Share\ **Created:** [January 21, 2009, 9:42pm UTC](https://boards.straightdope.com/t/stuff-that-only-sort-of-amazes-me/482361 "2009-01-21T21:42:21Z")\ **Posts on this page:** 8\ **Page:** 1
**Author:** ![Enright3](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/enright3/32/2897_2.png) [@Enright3](https://boards.straightdope.com/u/Enright3)\ **Post date:** [January 21, 2009, 9:42pm UTC](https://boards.straightdope.com/t/stuff-that-only-sort-of-amazes-me/482361/1 "2009-01-21T21:42:21Z")
OK, I didn’t want to hijack the [Stuff that amazes me](http://boards.straightdope.com/sdmb/showthread.php?t=502815) thread, I came in here to post a link to something that I thought was kind of neat about the physics of a two wheeled “Fred Flintstone” type of car, with a wheel on top of that. I know that doesn’t make much sense. [Look Here to see what i’m talking about.](http://www.i-am-bored.com/bored_link.cfm?link_id=37277) What way would you have guessed regarding the movement of the cart? ---
**Author:** ![Least\_Original\_User\_Name\_Ever](https://avatars.discourse-cdn.com/v4/letter/l/e480ec/32.png) [@Least\_Original\_User\_Name\_Ever](https://boards.straightdope.com/u/Least_Original_User_Name_Ever)\ **Post date:** [January 21, 2009, 10:10pm UTC](https://boards.straightdope.com/t/stuff-that-only-sort-of-amazes-me/482361/2 "2009-01-21T22:10:05Z")
I was with the plush Lion. I thought it’d go to the right. ---
**Author:** ![Joey\_P](https://avatars.discourse-cdn.com/v4/letter/j/919ad9/32.png) [@Joey\_P](https://boards.straightdope.com/u/Joey_P)\ **Post date:** [January 21, 2009, 10:27pm UTC](https://boards.straightdope.com/t/stuff-that-only-sort-of-amazes-me/482361/3 "2009-01-21T22:27:49Z")
[del]Weird, I guess you have to think of the ruler as another wheel up on top, which means the the the blue wheel will go the opposite way.[/del] I think the ruler isn’t turning the wheel so much as it’s pushing the entire cart. That is, the wheel would counter clockwise if you put your finger on the chassis and pushed the cart to the right. BUT, if you were to purposefully spin the wheel clockwise, _which is what SHOULD happen when something goes over the top of it from left to right_, I think the cart would go in the other direction. I think this is basically an optical illusion. He’s not turning the wheel, he’s pushing the cart. Let’s put it on a treadmill. ---
**Author:** ![Dreamy\_B](https://avatars.discourse-cdn.com/v4/letter/d/f07891/32.png) [@Dreamy\_B](https://boards.straightdope.com/u/Dreamy_B)\ **Post date:** [January 21, 2009, 10:37pm UTC](https://boards.straightdope.com/t/stuff-that-only-sort-of-amazes-me/482361/4 "2009-01-21T22:37:05Z")
I’m sort of amazed people say ‘anti-clockwise’. I’m very amazed that I knew that the cart would go the same direction as the ruler and much like Louise, I thought it would go to the right even though I didn’t exactly know why. ---
**Author:** ![Enright3](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/enright3/32/2897_2.png) [@Enright3](https://boards.straightdope.com/u/Enright3)\ **Post date:** [January 21, 2009, 10:40pm UTC](https://boards.straightdope.com/t/stuff-that-only-sort-of-amazes-me/482361/5 "2009-01-21T22:40:26Z")
> [@Joey\_P](#): > > I think this is basically an optical illusion. He’s not turning the wheel, he’s pushing the cart. > Let’s put it on a treadmill. It’s funny you said that. That’s what I thought too… as I was thinking of a jet on a treadmill. ---
**Author:** ![chacoguy](https://avatars.discourse-cdn.com/v4/letter/c/50afbb/32.png) [@chacoguy](https://boards.straightdope.com/u/chacoguy)\ **Post date:** [January 22, 2009, 12:04am UTC](https://boards.straightdope.com/t/stuff-that-only-sort-of-amazes-me/482361/6 "2009-01-22T00:04:16Z")
It has to do with the fact that the big blue wheel is in contact with the axle of the two spools. The fact that their diameter is smaller than the ‘wheel’ part of the spool ends, that is in contact, with the table’s surface. It effectively creates a gear box that accounts for the direction and speed difference. ---
**Author:** ![Rigamarole](https://avatars.discourse-cdn.com/v4/letter/r/77aa72/32.png) [@Rigamarole](https://boards.straightdope.com/u/Rigamarole)\ **Post date:** [January 22, 2009, 12:16am UTC](https://boards.straightdope.com/t/stuff-that-only-sort-of-amazes-me/482361/7 "2009-01-22T00:16:24Z")
> [@Dreamy\_B](#): > > I’m sort of amazed people say ‘anti-clockwise’. That threw me too, but the guy is British after all, you can’t put too much stock in what they say. Bear Grylls constantly says “disorientate” instead of plain old “disorient” and it drives me nuts. ---
**Author:** ![Joey\_P](https://avatars.discourse-cdn.com/v4/letter/j/919ad9/32.png) [@Joey\_P](https://boards.straightdope.com/u/Joey_P)\ **Post date:** [January 22, 2009, 1:01am UTC](https://boards.straightdope.com/t/stuff-that-only-sort-of-amazes-me/482361/8 "2009-01-22T01:01:53Z")
> [@chacoguy420](#): > > It has to do with the fact that the big blue wheel is in contact with the axle of the two spools. The fact that their diameter is smaller than the ‘wheel’ part of the spool ends, that is in contact, with the table’s surface. It effectively creates a gear box that accounts for the direction and speed difference. That takes into account the speed issue, but has nothing to do with the direction since the axles and wheels are a solid piece. If the big wheel was in contact with the wheels that are touching the table, the direction wouldn’t change.