## Tuesday, December 8, 2015

### The Physics of Santa

The biggest question in a kid’s mind is how Santa delivers all the gifts in a single night, so I thought I would calculate what Santa’s night would look like!
There are 1.9 billion children in the world, and 31.5% of the world is Christian. Therefore, Santa would have to deliver gifts to 600 million children, and assuming 3.5 children per household, he would deliver to 171 million households. Santa, if he were smart, would travel west so he would have 31 hours to deliver gifts, and would have to travel 133 million miles (assuming .75 miles between households). So, the sleigh would have to travel at 4.3 million mph, or 1,000 miles per second. Faster, in reality, since he would have to include stopping time at each house! The fastest man made vehicle on earth only moves at 27.4 miles per second. For acceleration:
x=vt+½at2
2.14×1011 m = 1.6×106 m/s (111600 s)+½(111600)2a
a=5.9 m/s2
Additionally, the sleigh would have to decelerate constantly, since it would constantly have to stop at houses.
Furthermore, the weight of the gifts on the sleigh would be enormous.  Assuming each child gets a 5 lb. gift, there would be 3 billion pounds on the sleigh, which is equal to 1.3 x 1010 N. Each of the 12 reindeer would then have to pull 1.6 x 109 N, not even including the mass of the sleigh itself and the overweight Santa Claus. And I don’t even know the physics behind a man trying to squeeze down a chimney!

Overall, Santa and his reindeer would definitely crash and burn without a little bit of magic.