Chemistry and Physics

How Fast Does Father Christmas Travel? Solved by Relativity…

The magic of Father Christmas has long mesmerised both children and adults alike, but just how does that jolly man make it around the world and deliver presents to 700 million children? It’s a feat we’d think to be surely impossible, however Dr Katy Sheen from the University of Exeter has the answers…

Santa and his crew of rowdy reindeer speed across the globe at such a speed that according to relativity theory will cause Father Christmas to shrink or become thinner in the direction he is travelling, thus allowing him to shimmy on down the chimney!

Relativity further explains as to why Father Christmas never ages as relativity causes the slow down of time. Dr. Sheen further calculated that the reindeer would have to travel at about 100 million kilometres per hour in order to deliver presents to every child on Christmas Eve- taking into account travelling across the different time zones.

Relativity is based on the idea that an objecting moving at a faster speed in relation to another shall cause time to slow. This can only be observed at light speed and hence has never been observed by the naked eye, however has led us to believe that Santa definitely does use relativity to his advantage as he speeds across the globe.

“100 million kilometres per hour”

Further to this is millions of children were good, then he may have to travel even faster! And at such a great speed it is no wonder that he cannot be seen by the naked eye on Christmas Eve.

This speed is more than 200,000 times faster than the fastest man on the planet,Usain Bolt!

Doppler effect would cause Santa to change colour due to the contraction of the light waves he releases as a moving particle at such high speeds. Doppler effect also explains as to why Santa can not be heard.

“change colour due to the contraction of the light waves”

Again in relation to the Doppler effect Santa and his crew approach, the sound of their bells shall go higher and higher until they become completely silent, as he would be moving beyond the human hearing range, making it inaudible to humans!

And there you go, Santa’s crazy Christmas Eve trip , solved by relativity!

Inga Becker-Hansen

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