**Thanksgivingkuh**

This year, Thanksigiving and Hannukah share a night and the
holiday has been named Thanksgivingkuh.
This won’t happen again for another 70,000 years so in its honor I am
looking at the physics behind a dreidel.
The question I asked was how much rotational kinetic energy does a small
plastic dreidel have when it is initially spun?

KE

_{rot }= ½ Iω^{2}
To calculate the moment of inertia of the dreidel I
approximated it as a solid cylinder which is not entirely correct but I think
it was the best option. The mass of a
plastic dreidel is about 0.00907 kg
according to a source online. The
diameter of the dreidel was approximately 1 inch which makes the radius is
0.0127 meters.

I= ½ mr

^{2}
I= ½ (0.00907kg)(0.0127m)

^{2}
I=7.314x10

^{-7}kgm^{2}
The initial angular velocity of the dreidel--it rotated
approximately 3 rotations per second, therefore:

3 rotations x (2π radians / one rotation) = 18.85 radians/second

Therefore the total rotational kinetic energy of the dreidel
when it was initially spun is:

KE = ½ (7.314x10

^{-7})(18.85)^{2}= 1.299 x 10^{-4}J
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