Physics: You spin me round round baby round round

What do bicycles, frisbees, yo-yos, hula hoops, dreidels, and even the earth have in common? They all spin, and so long as they spin the better they are at resisting what gravity is trying so hard to get them to do, which is tumble and fall. This week in physics, we played dreidel with a twist. Instead of playing dreidel for gelt, we played dreidel WITH gelt. The kids prepared 3 dreidels as follows: Each one had a plate with 4 coins attached either at the center or at the periphery in one of two possible patterns. The goal was to see which distribution of weight allowed the dreidel to spin the longest. Here's your clue: How is the weight distributed on a bicycle wheel? Is more of it at the center or along the periphery?

Physics: You spin me round round...

What do bicycles, frisbees, yo-yos, hula hoops, dreidels, and even the earth have in common? They all spin, and so long as they spin the better they are at resisting what gravity is trying so hard to get them to do, which is tumble and fall. The tendency of an object to resist change, is called inertia, or in the case of something spinning, rotational inertia. This week the kids were given plastic plates of different sizes, sticks, and weights (in the form of kippa clips) and were challenged to design the dreidel with the greatest rotational inertia...that's fancy talk for the dreidel that can spin the longest.