1) On which surface will a toy sled travel the furthest? 

carpet, polished wood, ice

2) On which surface will a toy sled travel the least distance? 

carpet, polished wood, ice

3) The stickier the surface, ... 

the greater the friction, the less the friction, the same level of friction

4) Which of the following is an example of trying to increase friction?

squirting oil into door hinges, spreading grit on icy roads, waxing the underneath of skis 

Item 3 is probably better as "The stickier the surface ... " instead of "The rougher the surface ..."   Our story is about sticky world, not rough world, and it may be a misconception to think of friction as roughness; it's not the same.   - Andy Posted by azucker at Aug 09, 2007 10:38

Hey guys, what the heck is a toy sled? How about a regular sled or a hockey puck?  Of course, kids in warm places probably don't even know about those... Posted by pburney at Sep 28, 2007 09:34