Fermi Questions C

[Tailsfan101]

Would anyone like to revive this thread?

When the last post was just two days ago, there's not really a need for revival quite yet. I would give it at least six days.
Someone's a little impatient.

[PM2017]

Would anyone like to revive this thread?

When the last post was just two days ago, there's not really a need for revival quite yet. I would give it at least six days.
Someone's a little impatient.

lol sorry. I thought it had been longer, I've just had one of those weeks. I also didn't read when I made my last post. But, now that I've done it... revive the thread? (lol)

[NeilMehta]

Someone's a little impatient.

uhh

But, now that I've done it... revive the thread? (lol)

Divide the word count of Dr. Seuss's "One Fish, Two Fish, Red Fish, Blue Fish" by the number of fish that are caught every year

[PM2017]

Someone's a little impatient.

uhh

But, now that I've done it... revive the thread? (lol)

Divide the word count of Dr. Seuss's "One Fish, Two Fish, Red Fish, Blue Fish" by the number of fish that are caught every year

lol I had posted a question earlier, that was ignored, but who cares lol

Attempt (Click to Show Hidden Text)

I think cat in the hat was like 250 words, and I'll assume this book to be the same, so 2 words. I'd say that people eat, on average 0 fish daily. With 8 billion people, this is 10 fish daily.Since there are 365 days, this becomes 12 fish per year. 2-12 = fermi answer of -10

Actual (Click to Show Hidden Text)

So the word count was actually 1308 (I think Dr. Seuss had to choose from 250 words, which he could reuse), so fermi value of 3. between 970 and 2700 billion fish are caught per year, so fermi factor of 12. 3-12 yields fermi answer of -9

How many walnuts are produced in the state of California in the last decade(2007-2017)?

[Tom_MS]

How many walnuts are produced in the state of California in the last decade(2007-2017)?

Attempt (Click to Show Hidden Text)

Okay. Given that I know nothing about the space required for walnuts to be grown or how long it takes to grow each one, I'll work off of more a demand => supply model. I'll start off by assuming that most California walnuts are consumed by people in the US. Let's say 20% of people (6e7) regularly consume walnuts. Of these people, the average consumption is 3 walnuts/day. 6e7*3e0*3.7e2 = 6.7e10 walnuts/country/year. I don't think this consumption has changed much over time, so just multiply by 1e1 and round to get a final answer of [highlight]12[/highlight]. This might be a bit high considering my estimations on average consumption, but I'm sticking with it because of industrial food manufacturing, waste, and so forth.

Answer (Click to Show Hidden Text)

Looking at a pdf of California walnut production has made me question my life choices, but here goes: According to this document, the mean walnut mass over the entire California area is roughly constant through time and is 21.1 grams. The mean output in tons of walnuts from 2007 to 2017 is 515,000 (assuming metric tons, but idk). This translates to 2.44*10^10 walnuts per year. Multiplied by 11 (forgot in attempt that the years listed total 11!) gives 2.7*10^11 walnuts, so [highlight]11[/highlight].

If all pillows in Kansas were stuffed with duck feathers, how many ducks would have to die in order to make them? I looked it up, and live plucking generally isn't done. Instead, feathers of ducks slaughtered for other purposes are generally used.

[PM2017]

How many walnuts are produced in the state of California in the last decade(2007-2017)?

Attempt (Click to Show Hidden Text)

Okay. Given that I know nothing about the space required for walnuts to be grown or how long it takes to grow each one, I'll work off of more a demand => supply model. I'll start off by assuming that most California walnuts are consumed by people in the US. Let's say 20% of people (6e7) regularly consume walnuts. Of these people, the average consumption is 3 walnuts/day. 6e7*3e0*3.7e2 = 6.7e10 walnuts/country/year. I don't think this consumption has changed much over time, so just multiply by 1e1 and round to get a final answer of [highlight]12[/highlight]. This might be a bit high considering my estimations on average consumption, but I'm sticking with it because of industrial food manufacturing, waste, and so forth.

Answer (Click to Show Hidden Text)

Looking at a pdf of California walnut production has made me question my life choices, but here goes: According to this document, the mean walnut mass over the entire California area is roughly constant through time and is 21.1 grams. The mean output in tons of walnuts from 2007 to 2017 is 515,000 (assuming metric tons, but idk). This translates to 2.44*10^10 walnuts per year. Multiplied by 11 (forgot in attempt that the years listed total 11!) gives 2.7*10^11 walnuts, so [highlight]11[/highlight].

If all pillows in Kansas were stuffed with duck feathers, how many ducks would have to die in order to make them? I looked it up, and live plucking generally isn't done. Instead, feathers of ducks slaughtered for other purposes are generally used.

Yeah, I made a mistake in that question. Meant for it to be multiplied by 11, but it makes virtually no difference.

Anyways,

Attempt (Click to Show Hidden Text)

Since there are e8 people in the US, i'd say there are about e6.5 people in kansas. My household has four people, but approximately a little over 10 pillows, so ill round e6.5 ppl to e7 pillows. I'll say one duck per pillow, so a fermi answer of [b]7 ducks[/b].

Actual (Click to Show Hidden Text)

There are approx 2.93 million ppl in Kansas (wow, my guesstimate was really accurate). Unfortunately, I have no idea how many pillows each person has, so I'm going to have to make an assumption. Do 3 pillows per person make sense? I think it does. So now, we have 8.8 million pillows in Kansas. Each duck has approximately 14,000 feathers (assuming pintail duck), and since I can't find how many feathers in a pillow, I'll multiply by 0.0082 grams per feather, to get 114.8 grams of feather per duck. pillows weigh approx 3.0 pounds, so that's 12 ducks per pillow. (yikes, that's a lot of dead ducks) so if we multiply 8.8e6 pillows by 12 ducks per pillow, we get 1.1e8, so Fermi answer[b] 8.[/b]

If an object were accelerating at 1g, how many seconds would it take to catch to an object going constantly at the maximum speed of the new horizons spacecraft if they both started at the same time? (assume the impossible situation that the acceleration of the object going at the spacecraft's velocity is immediate)

[Name]

If an object were accelerating at 1g, how many seconds would it take to catch to an object going constantly at the maximum speed of the new horizons spacecraft if they both started at the same time? (assume the impossible situation that the acceleration of the object going at the spacecraft's velocity is immediate)

Attempt (Click to Show Hidden Text)

Gonna assume New Horizons is going at around 10 km/s (Earth's escape velocity) Acceleration at 1 g is about  10m/s, which distance can be calculated by 5x^2 + 5x (I think?) At 10,000 seconds the object accelerating at 1 g force would be about 5 times the distance of New horizons at E4 seconds. Considering acceleration is slightly less and the rate increases E4 seconds

Actual (Click to Show Hidden Text)

New horizons is moving at about 10 km/s (slightly higher) and checking my equation seems to work so E4 seconds

Question: Suppose you developed a taste for fresh bird poop. Assuming a equal distribution of birds around the world, if you go outside and open your mouth towards the sky, how many galactic years will it take until a birds poop falls directly into your mouth?

[Unome]

Attempt (Click to Show Hidden Text)

Let's assume the average car is hit by bird poop once every 2 years on average. A car is about 6 m^2 and a human mouth facing upward is perhaps 1E-2 m^2, so 2*(6 / 0.01) = 12/E-2 = 1.2E3 years. A galactic year is ~2.5E8 years, therefore 1.2E3 / 2.5E8 = ~4.6E-6, so Fermi Answer: -6

Actual (Click to Show Hidden Text)

It seems that on average, birds produce about 50 g of droppings per day, which is about 5 droppings. There are about 3E11 birds worldwide, which we can divide by 5E14 to get 6E-4 birds per m^2 on average. I overestimated the size of an open mouth, which is actually closer to 2.5E-3 m^2, so 1.5E-6 of the time there will be a bird above a particular open mouth. With five drops a day, only about 5 seconds of that time per day counts toward bird droppings. Essentially, assume each bird poops simultaneously every 17280 seconds, and 1.5E-6 of those will fall in a mouth. This yields 1.152E10 seconds of time, which is 365 years, which is around 1.45E-6 to 1.6E-6 galactic years, hence Fermi Answer: -6 (yay!)

How many femtoliters per feet per meters is the radius of a typical adult alveolus?

Edit: Yes, I intended for those last two to be divisions.

[Name]

Attempt (Click to Show Hidden Text)

I'm assuming you mean a femto decimeter by meter by foot (correct me if I'm wrong because volumexlengthxlength doesn't make sense) So the volume of a decimeter foot meter is 3E-2 or 3E43 femto DMF in a meter cubed. Pretty sure alveolus are tiny air sacks. Pretty sure thier tiny (gonna assume volume of 100 mcm or about 12 would fit in a meter cubed. 43-12 is 31

Answer (Click to Show Hidden Text)

diameter equals 200 mcm radius .1 mm volume is 4E-3 mm 4E-12 meter or 2E11 per meter which is 32

Question: In a theoretical universe, a beam of light has a energy level of 100 joules per photon. Assuming it has a wavelength of the height of Angel Falls what is the speed of light in m/s

[Adi1008]

Attempt (Click to Show Hidden Text)

I'm assuming you mean a femto decimeter by meter by foot (correct me if I'm wrong because volumexlengthxlength doesn't make sense) So the volume of a decimeter foot meter is 3E-2 or 3E43 femto DMF in a meter cubed. Pretty sure alveolus are tiny air sacks. Pretty sure thier tiny (gonna assume volume of 100 mcm or about 12 would fit in a meter cubed. 43-12 is 31

Answer (Click to Show Hidden Text)

diameter equals 200 mcm radius .1 mm volume is 4E-3 mm 4E-12 meter or 2E11 per meter which is 32

Question: In a theoretical universe, a beam of light has a energy level of 100 joules per photon. Assuming it has a wavelength of the height of Angel Falls what is the speed of light in m/s

I have no idea how to do that question honestly

How far does an air molecule (assume at STP) travel on average before it hits another air molecule, in meters?