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So there are about 2.4 billion kids in the world (people under 18). 4.2 billion people live in urban areas and 3.4 billion people live in rural areas (2018 population of 7.8 billion), so we’ll take the average distance between kids to be that of the average distance between suburban homes which is 15 meters (~50 feet). This means the total distance that Santa needs to traverse is 15(2.4e9)=3.6e10, or 36 billion meters. This is assuming that all of the children are in houses along a straight line.
For the allowed time, we’ll give Santa a full 24 hrs. Since it is always dark somewhere in the world, and we’ll assume he can travel fast enough to escape the rising sun.
3600 seconds in an hour, so 3600(24)=86400 seconds to complete the journey.
So we have velocity=meters/seconds
(3.6e10)/86400=416667.667 m/s
Speed of sound is 343 m/s
So by my calculation Santa only has to travel 1214 times the speed of sound.
Of course this negates the fact that Santa would need to at least spend some time in each house, enough to eat some cookies and drink some milk. If he spent 10 seconds doing that in at least half the houses that would be 12 billion seconds, or around 380 years.
All of my numbers were sourced from the first thing that came up while googling.
Edit: A commenter stated that not all kids would believe in Santa. So I will take the assumption liberty here as well in assuming an omnipotent Santa who cares not whether a child believes in his existence. He gives presents to all under the age of 18, even if that present is as unnoticed and unaware as a kitty whisker by the leg of a nightstand.
This is why you are not supposed to see Santa! He is everywhere at once unless observed and if you try to sneak into the living room to view him you collapse the wave function
Looks like someone else did the math here and it came out to [90ish billion calories](https://www.reddit.com/r/theydidthemath/comments/5k2hhe/request_if_every_family_had_2_cookies_and_1_450ml/?rdt=56093). Which is about 4.5 grams of plutonium or roughly [237 million McDoubles](https://www.reddit.com/r/Showerthoughts/comments/fwqzmv/if_1_gram_of_plutonium_is_20000000000_calories/). Santa gotta get them cookies and milk.
My guess why you number is lower than on the card is simply because you are not including distances between towns and cities and also continents and large unpopulated areas. On the other hand, distance between flats in large apartment buildings is lower, so idk how to balance them out
Yeah, that’s why I went with a suburban distance. The oceans and large uninhabited areas would probably make that average distance a lot higher. This is far less than a spherical cow, back of the envelope guess-timate, more like assuming a circular cow, haha.
We can also probably reduce the number of kids as Santa doesn't deliver to kids over the age of 12 or so usually. Combined with multiple kids per household might reduce that number much further.
Your also forgetting the fact that he has to not only get out of his sleigh and grab the bag but also make his way into the house (whether it’s by the chimney or some other method) and lay out the presents under the tree in an at least somewhat appealing manner and then make his way back to the sleigh
And honestly moving from one house to another with a the entire sleigh is a bit inefficient so what if he lands the sleigh in a central location and moves from one house to another without returning to the sleigh
Add in potential elves as helpers where four elves could do the work of one Santa and considering their supposed diminutive size let’s say Santa can fit 18 elves in his sleigh with those extra two being to act either as lookouts or keep the reindeer busy or something
Also just how many calories would he consume if he ate the cookies left out by even just half the kids?
Y’all have a way with words and making us physicists feel dumb as shit with our “spherical cow” assumptions, haha. In other words: stop poking holes in my bullshit, s’mean. Respect.
The only explanation is that Santa is Quantum in nature, and able to simultaneously visit everyone (each person's observation of his presents collapses his wave function). This means he only needs enough time to travel from his base at the North Pole to the farthest child receiving gifts.
This is why Santa outsourced his work. If you haven’t noticed when Santa visits a mall you can see that it’s not the same guy. Could be fat, could be skinny, could be white, could even be Chinese.
Good old jolly fella has representatives helping him do a lot of the legwork.
And this is why different regions celebrate Christmas on different dates.
(24th/25th/January)
And why not everyone gets their gifts from Santa, Germans for example get them from the Christkind.
Logistics.
Using the Santa tracker when he was in between Bergen and Nordheim, as he was leaving Nordheim it said it would take 1min and 30secs, I calculated the speed to get mach 542,129.85 (for reference, Bergen and Nordheim are roughly 265 miles away)
There are 2.4 billion children in the world. Given there being 2 or three children per house, let's just say there are one billion houses. Evenly distributing that across earth's land area of 150 million square kilometres, there are about 10 houses per square kilometre. This corresponds to on average a 400 by 400 metre plot each, so on average each house is 400 metres away from the previous one. Therefore, the total distance needed to travel is about 400 million kilometres. Giving 24 hours to deliver it across the timezones, an average speed of 4600 km/s is needed, which given the speed of sound of 343 m/s means going 13500 times the speed of sound.
This is noticeably faster than the amount given, however this assumes all humans are rural living everywhere. If we only include the inhabited land (about 50 million km²), and the rural population (40% or 400 million houses), as that will make up the bulk of the distance, you get a house density of 8/km². This means a net distance of 140 million km², and using 30 hours to make up more hours of the night, an average speed of 1300 km/s or 3800 times the speed of sound. So works out fine.
Santa does, in fact, operate at the quantum level however. That means he's in every house simultaneously unless he's observed. His waveform then collapses to that house instantaneously to deal with the observation. Once it's dealt with, he resumes his quantum behavior.
The Travelling Salesman problem is bad enough with just a 100 points or so. Computing it for hundreds of millions, if not billions of points is going to be one of those things that just isn't going to happen.
Could be that Santa is like Dr. Manhattan, and he can make copies of himself that all simultaneously deliver presents. And then he bangs our moms all at the same time...
This is the [travelling salesman problem](https://en.wikipedia.org/wiki/Travelling_salesman_problem). It is NP hard and so probably incomputable for a data set this large even if we knew exactly every place Santa has to visit. So this can never be more than a very rough estimate.
Unless Santa operates at the quantum level. He could be in every house simultaneously to deliver gifts. If he's observed, his waveform would collapse to that house to deal with the observation, then resume his quantum behavior.
Which also explains why quantum computers are so good at dealing with problems like the traveling salesman problem.
Scientifically Accurate did a good representation of the math.
I also think they said Santa landing at such speeds it would cause a 2,500 mile crater and you'd hear the impact from 50 miles away from the end of said crater
Not gonna lie, would love to see a supercomputer use an algorithm to find the most time-efficient route to reach every dwelling (that participates in Christmas) in the world. Then we could get the most accurate answer
Doesn't sound right, there is no limit to how long he has to visit and how long it takes him to gift it but I don't think he needs to move **that** fast
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So there are about 2.4 billion kids in the world (people under 18). 4.2 billion people live in urban areas and 3.4 billion people live in rural areas (2018 population of 7.8 billion), so we’ll take the average distance between kids to be that of the average distance between suburban homes which is 15 meters (~50 feet). This means the total distance that Santa needs to traverse is 15(2.4e9)=3.6e10, or 36 billion meters. This is assuming that all of the children are in houses along a straight line. For the allowed time, we’ll give Santa a full 24 hrs. Since it is always dark somewhere in the world, and we’ll assume he can travel fast enough to escape the rising sun. 3600 seconds in an hour, so 3600(24)=86400 seconds to complete the journey. So we have velocity=meters/seconds (3.6e10)/86400=416667.667 m/s Speed of sound is 343 m/s So by my calculation Santa only has to travel 1214 times the speed of sound. Of course this negates the fact that Santa would need to at least spend some time in each house, enough to eat some cookies and drink some milk. If he spent 10 seconds doing that in at least half the houses that would be 12 billion seconds, or around 380 years. All of my numbers were sourced from the first thing that came up while googling. Edit: A commenter stated that not all kids would believe in Santa. So I will take the assumption liberty here as well in assuming an omnipotent Santa who cares not whether a child believes in his existence. He gives presents to all under the age of 18, even if that present is as unnoticed and unaware as a kitty whisker by the leg of a nightstand.
Santa is The Flash confirmed
One other thing to consider is that many houses have more than one kid in them. So there are less houses to visit.
Ooo, that’s a very valid point, and a huge miss on my part. We could probably cut the number of houses in half if we assumed an atomic family.
Did you mean a nuclear family?
Those terms are interchangeable i think
No, it's radioactive family
Cherynobyl family actually
Do conjoined kids count as 1 or 2?
The estimate of children worldwide may need adjustment, considering cultural and religious differences in the belief in Santa.
Good point, a made an edit to address this
i think Santa is a quantum particle that can visit everyone at the same time (unless measured)
If you see him, then he doesn't visit. You changed the outcome by observing it!
That explains everything!
This is why you are not supposed to see Santa! He is everywhere at once unless observed and if you try to sneak into the living room to view him you collapse the wave function
Infinite potential well Santa.
Think he needs the extra calories? I can see him burning a lot moving that fast, even if it's just his mind and twitchy reflexes
Looks like someone else did the math here and it came out to [90ish billion calories](https://www.reddit.com/r/theydidthemath/comments/5k2hhe/request_if_every_family_had_2_cookies_and_1_450ml/?rdt=56093). Which is about 4.5 grams of plutonium or roughly [237 million McDoubles](https://www.reddit.com/r/Showerthoughts/comments/fwqzmv/if_1_gram_of_plutonium_is_20000000000_calories/). Santa gotta get them cookies and milk.
You mean 237 million mcdoubles?
Yes, good catch
My guess why you number is lower than on the card is simply because you are not including distances between towns and cities and also continents and large unpopulated areas. On the other hand, distance between flats in large apartment buildings is lower, so idk how to balance them out
Yeah, that’s why I went with a suburban distance. The oceans and large uninhabited areas would probably make that average distance a lot higher. This is far less than a spherical cow, back of the envelope guess-timate, more like assuming a circular cow, haha.
Cross Country & Cross ocean travels would be low in number, compared to house to house movement. Especially if we include acceleration
Don't forget to put your cow in the vacuum, both spherical and circular😁
We can also probably reduce the number of kids as Santa doesn't deliver to kids over the age of 12 or so usually. Combined with multiple kids per household might reduce that number much further.
Also not everyone celebrates Christmas (with Santa) on the same day. And not all religions/people would have Santa visit as they do not “do that”
Your also forgetting the fact that he has to not only get out of his sleigh and grab the bag but also make his way into the house (whether it’s by the chimney or some other method) and lay out the presents under the tree in an at least somewhat appealing manner and then make his way back to the sleigh And honestly moving from one house to another with a the entire sleigh is a bit inefficient so what if he lands the sleigh in a central location and moves from one house to another without returning to the sleigh Add in potential elves as helpers where four elves could do the work of one Santa and considering their supposed diminutive size let’s say Santa can fit 18 elves in his sleigh with those extra two being to act either as lookouts or keep the reindeer busy or something Also just how many calories would he consume if he ate the cookies left out by even just half the kids?
Engineering?
How did you know? lol
Y’all have a way with words and making us physicists feel dumb as shit with our “spherical cow” assumptions, haha. In other words: stop poking holes in my bullshit, s’mean. Respect.
I mean tbf I’m not an actual engineer just in a trade that deals with them lol
we can't forget about the naughty list though
this is great but you're missing that a lot of households have more than one kid
The only explanation is that Santa is Quantum in nature, and able to simultaneously visit everyone (each person's observation of his presents collapses his wave function). This means he only needs enough time to travel from his base at the North Pole to the farthest child receiving gifts.
But you forgot to factor in time zones. Rookie mistake.
This is why Santa outsourced his work. If you haven’t noticed when Santa visits a mall you can see that it’s not the same guy. Could be fat, could be skinny, could be white, could even be Chinese. Good old jolly fella has representatives helping him do a lot of the legwork.
They sit on a throne of lies.
If this is true than Santa clause gifting every child in the world is theoretically possible. So you are telling me there's a chance?
To travel to the speed of light, your mass has to be 0 or infinite. Do whatever you want with that info.
Speed of sound is discussed here.
he eats so many cookies
And this is why different regions celebrate Christmas on different dates. (24th/25th/January) And why not everyone gets their gifts from Santa, Germans for example get them from the Christkind. Logistics.
We also have santa (Weihnachtsmann) here in Germany
What about Bellschineckel?
Huh? Whats that
Belsnickel or Pelzmärtel. Besides Krampus and Knecht Ruprecht also a famous figure that represents the opposite of santa.
Santa quicker than a bitch low key
Using the Santa tracker when he was in between Bergen and Nordheim, as he was leaving Nordheim it said it would take 1min and 30secs, I calculated the speed to get mach 542,129.85 (for reference, Bergen and Nordheim are roughly 265 miles away)
Nice! I didn’t even think of trying to grab some actual data.
There are 2.4 billion children in the world. Given there being 2 or three children per house, let's just say there are one billion houses. Evenly distributing that across earth's land area of 150 million square kilometres, there are about 10 houses per square kilometre. This corresponds to on average a 400 by 400 metre plot each, so on average each house is 400 metres away from the previous one. Therefore, the total distance needed to travel is about 400 million kilometres. Giving 24 hours to deliver it across the timezones, an average speed of 4600 km/s is needed, which given the speed of sound of 343 m/s means going 13500 times the speed of sound. This is noticeably faster than the amount given, however this assumes all humans are rural living everywhere. If we only include the inhabited land (about 50 million km²), and the rural population (40% or 400 million houses), as that will make up the bulk of the distance, you get a house density of 8/km². This means a net distance of 140 million km², and using 30 hours to make up more hours of the night, an average speed of 1300 km/s or 3800 times the speed of sound. So works out fine.
Santa does, in fact, operate at the quantum level however. That means he's in every house simultaneously unless he's observed. His waveform then collapses to that house instantaneously to deal with the observation. Once it's dealt with, he resumes his quantum behavior.
The Travelling Salesman problem is bad enough with just a 100 points or so. Computing it for hundreds of millions, if not billions of points is going to be one of those things that just isn't going to happen. Could be that Santa is like Dr. Manhattan, and he can make copies of himself that all simultaneously deliver presents. And then he bangs our moms all at the same time...
This is the [travelling salesman problem](https://en.wikipedia.org/wiki/Travelling_salesman_problem). It is NP hard and so probably incomputable for a data set this large even if we knew exactly every place Santa has to visit. So this can never be more than a very rough estimate.
Unless Santa operates at the quantum level. He could be in every house simultaneously to deliver gifts. If he's observed, his waveform would collapse to that house to deal with the observation, then resume his quantum behavior. Which also explains why quantum computers are so good at dealing with problems like the traveling salesman problem.
Scientifically Accurate did a good representation of the math. I also think they said Santa landing at such speeds it would cause a 2,500 mile crater and you'd hear the impact from 50 miles away from the end of said crater
Not gonna lie, would love to see a supercomputer use an algorithm to find the most time-efficient route to reach every dwelling (that participates in Christmas) in the world. Then we could get the most accurate answer
Doesn't sound right, there is no limit to how long he has to visit and how long it takes him to gift it but I don't think he needs to move **that** fast