Give me a challenge

[Dominatus]

Okay, gonna keep this short. I woke up with a headache, was late getting out the door and I don't have any caffeine. (Thanks health regulations) someone give me something to puzzle over and wake my brain up so I have some chance of learning today. Much appreciated!

[tutrakan4e]

If you are what you eat, then are cannibals the only real humans?

[SiliconPyro]

Plan a KSP mission to a body outside Kerbin's SOI on paper. List every part, calculate your full DeltaV budget and document the full mission parameters including where you intend to land. If you're good, it'll actually work!

[Napaeozapus]

Go the entire day without dissociating. That is keep your mind in the moment and not elsweyr.

[VirtualCLD]

Here's a fairly common brain teaser my thesis advisor gave me once. If you get stuck you could Google it.

In the US, motor vehicle (liquid) fuel efficiency is often stated as miles per gallon. Of course a mile is a unit of length and a gallon is a unit of volume. A unit of volume can be expressed a cubic unit of length. To use a metric example, a centimeter is a unit of length, a milliliter is a unit of volume, but a milliliter is equal to one cubic centimeter. So you can express fuel efficiency as a length/length^3 = 1/length^2 which is another way of saying 1/(some area). What is the relationship between fuel efficiency and the inverse of some surface area? Or another way of asking it is: What does the inverse area represent in real life terms?

[Wanderfound]

This is just straight up learnin' rather than a puzzle, but this is the first resource that I used to point my Introduction to Neuroscience students towards.

Scicurious' Neuro 101: http://scientopia.org/blogs/scicurious/science-101/

[peadar1987]

Why are manhole covers round?

[EdFred]

Why are manhole covers round?

So it's "impossible" for them to fall through the hole.

[peadar1987]

So it's "impossible" for them to fall through the hole.

Ten points, go to the top of the class.

[Red Iron Crown]

Here's a fairly common brain teaser my thesis advisor gave me once. If you get stuck you could Google it.

In the US, motor vehicle (liquid) fuel efficiency is often stated as miles per gallon. Of course a mile is a unit of length and a gallon is a unit of volume. A unit of volume can be expressed a cubic unit of length. To use a metric example, a centimeter is a unit of length, a milliliter is a unit of volume, but a milliliter is equal to one cubic centimeter. So you can express fuel efficiency as a length/length^3 = 1/length^2 which is another way of saying 1/(some area). What is the relationship between fuel efficiency and the inverse of some surface area? Or another way of asking it is: What does the inverse area represent in real life terms?

I think it would be the cross sectional area of the fuel pipe if the fuel flows at the rate of travel. (Didn't google, just a guess.)

[LLlAMnYP]

Here's a fairly common brain teaser my thesis advisor gave me once. If you get stuck you could Google it.

In the US, motor vehicle (liquid) fuel efficiency is often stated as miles per gallon. Of course a mile is a unit of length and a gallon is a unit of volume. A unit of volume can be expressed a cubic unit of length. To use a metric example, a centimeter is a unit of length, a milliliter is a unit of volume, but a milliliter is equal to one cubic centimeter. So you can express fuel efficiency as a length/length^3 = 1/length^2 which is another way of saying 1/(some area). What is the relationship between fuel efficiency and the inverse of some surface area? Or another way of asking it is: What does the inverse area represent in real life terms?

Ha! Good one! So what-if.xkcd has done this using the european way of representing fuel consumption (liters per 100km, or a unit of area). That surface area is basically the answer to the question "if instead of burning fuel a car leaves a stream of consumed fuel behind it, what would the cross section of that stream be?". So I tried to consider, what significance does the inverse quantity have.

Imagine, you have an infinitely long channel of fuel along the roadside with a cross-section of unit area. On the road you have several cars which have no fuel tanks, but instead have scoops picking up fuel from this channel. This inverse area is "how many cars will this channel be able to sustain".

Crazy thought experiments

[VirtualCLD]

I think it would be the cross sectional area of the fuel pipe if the fuel flows at the rate of travel. (Didn't google, just a guess.)

Ha! Good one! So what-if.xkcd has done this using the european way of representing fuel consumption (liters per 100km, or a unit of area). That surface area is basically the answer to the question "if instead of burning fuel a car leaves a stream of consumed fuel behind it, what would the cross section of that stream be?". So I tried to consider, what significance does the inverse quantity have.

Imagine, you have an infinitely long channel of fuel along the roadside with a cross-section of unit area. On the road you have several cars which have no fuel tanks, but instead have scoops picking up fuel from this channel. This inverse area is "how many cars will this channel be able to sustain".

Crazy thought experiments

Good job! Red Iron, you have good intuition with your critical thinking.