theydidthemath

[Request] If you stopped paying all former US politicians and evenly distributed the savings amongst soldiers and age pensioners - how much would their income increase per annum?

[Request] If you stopped paying all former US politicians and evenly distributed the savings amongst soldiers and age pensioners - how much would their income increase per annum?

It would be negligible. According to the VA, there are about 20 million veterans. That means a thousand former presidents donating their money to vets would end up giving them $22.50 a year, each. Ten thousand congressmen would still only be around $100 per person.

Instead of trying to cut off pensions of retired politicians, try emailing or calling the current ones and asking for decreased spending in areas you don't care about and increased spending in areas you do. Alternatively, find out which lobbying groups support your ideals and donate to them.

http://www.house.gov/representatives/find/ http://www.opensecrets.org

There are 435 1145 former congressmen and 5 former presidents. In total, cancelling their salaries according to this graphic would save ~$78 $201.5 million per year.

There are 1,281,900 active duty military and 41.2 million retired people claiming social security.

$78 $201.5 million into 42.5 million is $1.83 $4.74 per person.

EDIT: /u/F4RM3RR pointed out that there are more than 435 former congressmen. Updating the math still makes for a ridiculous number. Everyone who pointed out that 435 is a hugely coincidental number makes me wonder why I didn't notice this last night.

Sources: https://www.opensecrets.org/revolving/top.php?display=Z https://www.ssa.gov/news/press/factsheets/basicfact-alt.pdf

And then you find out how much of the budget is non-discretionary spending and you get frustrated with our whole system and start drinking the pain away every night, banishing it for a few blessed hours until it returns and torments you until you feed it more of that sweet elixir of sanity. Day after day, week after week. Year after year.

Anyway, yeah a lot of spending isn't subject to cuts.

Thank you! This will greatly help me in calling bullshit on my uncle!

[Request] how fast would a skateboard be traveling before this happens to a wheel?

source video

Alright, so we can finally calculate this from scratch. At the 20 second mark of the , we see a DSLR camera with a macro lens. That's the most likely camera to be filming the slow motion shots. Based on the Face-slap in the intro, and comparing it to other 240fps slomo slap videos, I am pretty confident this camera is filming at 720p @ 240fps. I have further conviction that this is not filed on a phantom or other super-high-fps because of the sound in the slap video. You can see the camera has a microphone attachment. Unlike video, audio doesn't translate well when you slow it down more than 10x.

So we have the FPS. I didn't bother researching this EXACT skateboard, but the wheels look standard to me, and standard wheels tend to be 52mm in diameter.

The tedious part is watching the video frame by frame for the few seconds leading up to the expansion, but you can very clearly see the small black logo on the wheel going less than one rotation per frame, slowly exceeding 1 per frame, then approaching 2 per frame, then approaching 3 per frame. At 3 rotations per frame, there are about 15 frames in a row where the rotation is almost exactly 3 rotations per frame, and the wheel begins to expand.

So where does that leave us? At 3 rotations per frame and 240 frames per second the wheel is spinning at 720 cycles per second. The circumference of the wheel is given by pi times diameter giving 3.14 x 52 mm = 163 mm. All that's left to do is multiply and get 163 mm x 720Hz = 117360 mm/s = 117 m/s = 263 mph

Sorta surprised at how slow this is, but then again skateboards were never designed to go over 30, nevermind approach 300.

And if you're finding 263 mph to be as disappointingly slow as I found it, just know that 720Hz is really fast. It's 43,200 rpm, which is well above what's required to shatter a cd(~23,000 rpm) and also destroy fidget spinners(~21,000 rpm)

I'm also entertaining the possibility that the video was taken at 120FPS, which would mean all the speeds are reduced by half, but that would be too disappointing. I guess we won't know 100% until they get back to me on what camera they used for it! =)

EDIT: People are asking how I know it's 3 rotations per frame. /u/inter_zone pointed out that the logo should stretch proportionally to the speed. The way you know you have reached a steady X cycles per second is that the logo stops moving much from frame to frame for a few frames. These are the three frames where we hit 1 Rotation per frame, 2 Rotation per frame, 3 Rotation per frame. This image is further evidence. The first logo is about 1/6 of the cycle, the second is about 2/6 and the third is about 3/6. I'm not 100% on my markings, but I tried my best to boost the logo in Photoshop without destroying the images. =)

I couldn't find the rpm for slateboard bearings but I did find the rpm for a cd to explode, about 37,000 rotations per minute, so since the skateboard is smaller and thicker I'll assume it would take about 50,000 rpm. A fast wheel is about 60mm in diameter. That's 188mm in circumference. So you travel 188mm per rotation. 9,400,000mm covered in a minute. 9,400 meters in a minute. 9.4 kilometers in a minute. So 564 kilometers per hour or 350 mph. Please double check me, Im new to this.

We could also look at the speed of the water itself coming out of the jet nozzle - a couple different sites I looked at put the speed at 600-900mph for cutting waterjets like that.

Considering the speed lost due to energy transfer here (we'd be looking at the dynamic friction of the water passing over the wheel), I think your estimate is actually pretty accurate.

Also, cool gif, OP.

Great answer, this should be the top comment. How did you determine 3 rotations per frame?

[Off-site] Futurama does the math

[Off-site] Futurama does the math

This is some serious math, too. It shows that 211 - 1 (which is 2047) is not a prime number, because it's 23*89.

Numbers of the form 2p - 1 for prime p are called Mersenne numbers, and often they are prime. They are interesting for several reasons; for one thing, they are very big, so all the largest prime numbers we know are Mersenne primes.

But just because a number fits the formula does not guarantee it is prime. 2047 proves this - it is the smallest Mersenne number that is not actually a Mersenne prime.

The Futurama writers certainly like their math!

Futurama and the first half or so of the Simpsons probably had some of the smartest humor on television, most of which barely gets noticed because it's hidden behind the "lowest common denominator" humor (which is still hilarious).

Good god I love these shows. They're like Pixar movies. I started watching both of them when I was relatively young, and I always get more and more jokes when I go back to rewatch them.

Sorry for the rant, I'm pretty messed up at the moment. But I always get so excited when I find out little shit like this happens in my favorite shows.

Too bad Futurama won't be on Netflix anymore. :(

i'll ruin for you! Chuck's Fuck and Suck

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[Self] When two engineers discuss earthquakes.

[Self] When two engineers discuss earthquakes.

The most engineering thing you can say. "I don't want to do the math." ... "So I did the math..."

You have no idea how often those words go together lol

I presume yall were talking about Charleston SC? I'm currently downtown, and would definiately not appreciate an earthquake right now...

The energy output of this earthquake is 600 times the output of a Type II supernova, as in an exploding star ten times larger than our sun. That energy can't be contained in the vibration of the Earth's crust, and would rapidly become heat and light due to entropy, friction, and all the regular culprits for movement becoming radiation.

A Type II supernova occurring where the Earth is now would destroy the moon, boil away the surface of the inner planets in our solar system, and strip away most of the atmosphere of our gas giants.

Let's consider the gamma radiation caused by rapidly accelerating the electron stripped, and therefore ionically charged, atomic nucleii of the Earth's crust to the high speeds of this explosion. This gamma radiation alone would cause mass extinctions of any life that might have existed in solar systems of the 2000 star systems in our local galactic neighborhood, including any life on the surface of any of the 33 exoplanets we have discovered so far in these systems.

A magnitude 22 earthquake would make the expanding, glowing plasma that was once earth briefly among the brightest lights in our Galaxy.

[request] g forces experienced by passengers on this train. And would you need to be buckled in?

The 6 trains do about a full rotation in the 2.5 second gif. I'm just guessing that the train length with 4 doors is about 18 metres. That makes a 108m circumference hexagon with a radius of about 17m, traveling at 43.2 m/s linearly. Assumed 54 people sitting, at 80 kg on average, with each train car weighing 38000 kg, that totals to 247920 kg. Centrifugal force is Mrw2 .

So for a rough estimate, about 11.2 g or 27 meganewtons of force.

A hard slap on the face may briefly impose hundreds of g locally but not produce any real damage; a constant 16 g for a minute, however, may be deadly.

https://en.wikipedia.org/wiki/G-force#Human_tolerance

Elsewhere in the article it says that a typical person can withstand about 5 g in the positive direction (the direction in the gif) before losing consciousness.

So using your numbers, it sounds like pretty much everyone on the train is unconscious, and the forces are at the very least near the deadly range for a typical person.

To give some more perspective....a well-trained fighter pilot with a G-suit can pull 9 Gs for short periods of time without passing out.

The upper barrier, assuming pure g force (and not vibrations tearing you apart) is 16-20g, where you have bloodflow issues and similar.

[Off-Site] Man claims to finish 500 episodes in a week, gets called out

[Off-Site] Man claims to finish 500 episodes in a week, gets called out

This actually has a different explaination from what others are saying. Naruto is a show that has a lot of episodes that are not from the original content, the manga. These episodes are often referred to as filler, and many people just skip them. We can find what episodes are filler here: http://www.animefillerlist.com/shows/naruto, http://www.animefillerlist.com/shows/naruto-shippuden.

The amount of non-filler episodes is 124 for Naruto, and for Naruto Shippuden 277, according to my count (which may be off by a few, but is largely accurate). This leads to a total of 401 episodes (note that the original post is also way off on the total amount of episodes, which is 720). keeping the average of 23 minutes an episode leads to a total watch time of 9,223 minutes, or 6.4 days. Through the openings and endings you could probably cut out another 2-3 minutes an episode, so let's take 3 to give him the benefit of the doubt. This would be 8,020 minutes, or 5.6 days. This would just barely be possible on minimal sleep, without having to go out for anything. So while now technically possible, I still call BS on this one.

EDIT: I realise there are many ways to watch the show, however claiming you watched the show in a week disqualifies most of them in my opinion. I did the math for the scenario's that gave him the best benefit of the doubt I could without undermining his claim.

Plus, some people like to watch anime at 1.25 speed for OPTIMAL EPISODE GRIND

I watch Naruto at 1.6 because I actually like it at that speed if it's the dub version. Makes it look smoother and the combat faster paced

I don't even understand what he has to gain from lying about this. Like he's bragging he has less of a life than the other guy?

[request] How many times would it ACTUALLY fit, assuming it had to keep its spherical shape?

[request] How many times would it ACTUALLY fit, assuming it had to keep its spherical shape?

According to wikipedia, the densest packing of spheres you can get uses approximately 74% of the volume. So although Uranus has a volume of 6.833 x 1013 km3, we can only store 5.06 x 1013 km3 worth of Earths in there, assuming the size ratios are perfect for the most dense packing to be possible. Earth has a volume of 1.1 x 1012 km3. We can therefore fit 46 Earths within Uranus if we have to keep their shape rather than just cram the volume in.

Probably won't fit - the densest packing only achieves this packing if it fills all space. You'll need larger gaps at the surface of Uranus.

Edit: Only 31 fit, see the other comment chain.

Packing problems are definitely not my expertise

I'm a virgin too.

The reference has a table up to 72 spheres.

For 0.2512, we can use 31 spheres (0.2531162).

31 Earths fit in.

[Request] How large would this bee be growing each year?

[Request] How large would this bee be growing each year?
According to National Geographic, a honeybee has a size of 0.6 in. which is approximately 1.5 cm. Its height is about 1/6 of its length so I'm going to assume the initial height is 0.25 cm. In 2034, it is as tall as a man which would be 170 cm Human height on wikipedia.

If you assume it grows linearly each year, the equation for the size would be 9.98529t + 0.25

If you assume it grows exponentially, the equation for the size would be 0.25*1.46764t

Usually, however, the exponential growth model is a better estimation for a growth model so I would tell you that the amount it grows increases over the year exponentially.

For those who prefer visuals, here's the graph of linear growth and the graph of exponential growth generated using wolfram alpha.

EDIT: formatting and graphs.

According to National Geographic, a honeybee has a size of 0.6 in. which is approximately 1.5 cm. Its height is about 1/6 of its length so I'm going to assume the initial height is 0.25 cm. In 2034, it is as tall as a man which would be 170 cm Human height on wikipedia.

If you assume it grows linearly each year, the equation for the size would be 9.98529t + 0.25

If you assume it grows exponentially, the equation for the size would be 0.25*1.46764t

Usually, however, the exponential growth model is a better estimation for a growth model so I would tell you that the amount it grows increases over the year exponentially.

For those who prefer visuals, here's the graph of and the graph of exponential growth generated using wolfram alpha.

EDIT: formatting and graphs.

Your graphs don't have units on their axes :(

yeah I generated using wolfram alpha so there are limitations. y axis is height in cm and x axis is time in years.

Not an ansver but there is kind of two answers, they could grow by a set amount or to the power of something [xy] but I am not great at math so this might be incorrect

[request] What fontsize is Sessions using here?

[request] What fontsize is Sessions using here?

Edit: It appears my cap-height was off. Thanks to u/donnonun for the correction here

Original comment:

If the paper is letter-size (8.5inx11in):

Width of paper is ~210 px, cap height of letters appears to be ~7px

(8.5in/210px)*7px = 0.2833in

72point = 1in

72*0.2833 = ~ 20.4pt type

I'd round it to 20, which seems like a reasonably even number.

Good work!

It's more likely to be 21pt, as that is a common preset for anyone not manually typesetting.

libre office

There are dozens of us!!

[Request] Is this bullshit or actually true in some way? Or how clode is it to the truth? Can someone please do the math

[Request] Is this bullshit or actually true in some way? Or how clode is it to the truth? Can someone please do the math

It is bullshit.

Global military spending is estimated to be $1.7 trillion in 2016. List by country. Scaling down that would be $37 billion for 8 days. You cannot really just stop spending money for 8 days and then go on as before, but let's ignore that part.

There are 1.8 billion children under 15, but we don't want to start with toddlers, let's say we want to give education to 1 billion of them. That is $37 per person. For 12 years of education? Yeah... no way.

Another comparison: Global spending on education is 4.7% of the GDP, twice the global spending on military. With 8 days of military spendings we can financy the current education system for 4 days.

Would it make sense if we only considered those children who currently have no access to an education? That would cut the numbers by a large amount

70 million? 72 million here. Most of them are in countries where things are quite cheap (measured in $), and we now have $530/child, or $44 per year. Still not enough, but if 88% come from local sources as in the article, and if that stays true with our now increased funding, we have $1/day, roughly consistent with the $1.18 number there.

With a lot of goodwill, we can find numbers that have some relation to the claim in OP's image.

Kind of misleading if they've just taken the worlds total spending on military and divided it by 365 to find the cost of the military per day. Lots of military expenses are not going to be day-to-day costs

Try one of these subthreads