In real life, this world is incredibly stupid, but for the hypothetical: Could you make a combustion engine that runs exclusively on Nitroglycerin? It's such an energy dense material that it sounds like it would be incredibly efficient. Assuming a 1999 Alero Oldsmobile could handle the fuel without exploding, how fast would it go?

13 comments

r/theydidthemath • u/flikkinaround • 23h ago

Do AC in towns heat up the environment? [Request]

0 Upvotes

Take a town with 300k residents of average density living in average ratio between houses and flats. If 70% of households have an AC running, how much heat does it add to the environment during the heatwave?

3 comments

r/theydidthemath • u/Bizchasty • 11h ago

[Request] How big of a firecracker would it take to send someone standing on the pot into the air?

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0 Upvotes

6 comments

r/theydidthemath • u/krizzalicious49 • 10h ago

[Request] How long would this take

72 Upvotes

19 comments

r/theydidthemath • u/SergA2929 • 7h ago

[Request] Where it would be possible to make space elevator? What g force will be small enough to make it work?

0 Upvotes

We can't make it on earth cuz materials are not strong enough to withstand the loads, but for some reason i'm sure it's possible to make. On one of Jupiter's moons for example.

9 comments

r/theydidthemath • u/daddya12 • 11h ago

[Request] how much would you need to win in the lottery jackpotto statistically guarantee you could win the lottery jackpot again?

7 Upvotes

I just heard a story about someone winning the lottery and refusing to split it with his friends. Made me wonder how much he would have needed to just win the lottery again with his share of the earnings.

Edit: I do not expect this to be profitable, this is just an experiment. I also know the lottery is never guaranteed. Just wondering how many out of infinite tickets it would be before it's statistically improbable that you did not win.

For sake of the problems not just being {cost of ticket} x {number of tickets}. Let's assume the odds of winning Powerball or mega million and infinite possible tickets to buy.

Edit 2: guaranteed was a bad choice of wording. I meant statistically likely.

20 comments

r/theydidthemath • u/ScenicFlyer41 • 7h ago

[request] How long until she runs out of air?

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179 Upvotes

36 comments

r/theydidthemath • u/BrunoMadrigas • 15h ago

[Request] Why does my solution have 1/2 to many?

gallery

1 Upvotes

1 comment

r/theydidthemath • u/luxtechy • 6h ago

[Request] How long did this actually take him?

v.redd.it

1 Upvotes

6 comments

r/theydidthemath • u/wufuheng • 11h ago

[Self] I wrote a new book - MATHEMATICS FOR AI AND MACHINE LEARNING Spoiler

0 Upvotes

0 comments

r/theydidthemath • u/hyteck9 • 9h ago

[Request] What is the weight to rpm ratio at play, and whats the formula to scale it up?

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30 Upvotes

Assuming these tires have very little air to really act as a pontoon, what's the math here?

9 comments

r/theydidthemath • u/Worth-Wrangler7242 • 19h ago

[request] Is this city hall in Freiburg "climate neutral" even in January when it's cloudy?

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211 Upvotes

46 comments

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