Prompt:
Suppose if there is a bird, it could fly thousands of miles, across the Pacific Ocean, and what it needs is a single tree branch. When flying in the air, the bird will carry the branch by mouth, and when it is tired of flying, it puts the branch on the ocean, and rest on it. While hungry, the bird may hunt for fishes on the branch, and sleep on the branch if tired.
Who would have thought, the bird have successfully crossed the ocean, with only a single tree branch at hand. How did the bird do that?
If the bird carried the entire property of the nest, the eggs, the food --- Then is it even possible for the same bird to perform such a feat anymore?
Student:
As a student studying STEM, I am literally petrified seeing this prompt.
I want to slap people! I want to slap the teacher who gave this prompt, on behalf of my Physics teacher.
For a bird, to cross the Pacific with a single branch within its mouth --- What kind of obscure IQ can make up this story? I have no idea how strong and magical is the bird beloging to the prompt-giving teacher. For a normal person I must be skeptical about this topic. I don't care personally, about how a bird with a branch in its mouth would deal with its mate; I don't care personally, about how a bird that doesn't swim can merely using a branch as a step to catch fishes with; I also don't care personally, about whether if the waves in the ocean will flip the branch or anything. I just want to ask you all one question:
How big must the branch be to support a bird afloat on the water? How big? As thin as a metal wire? As thick as a chopstick?
I want to teach you a equation about buoyancy, the slap-needing prompt-giving teacher. If you want a piece of wood to support a bird on the water, then this equation must be followed (For respect to your IQ, I will not be using any symbols or letters):
Wood's gravitational pressure - Wood's gravity + Bird's gravitational pressure
Let's just imagine if the wood is used to its maximum and it is just completely stepped underwater by the bird, Then we can get this:
Water's density * Wood's volume * Gravitational constant - Wood's density * Wood's volume * Gravitational constant + Bird's mass * Gravitational constant
Combining like terms and thus simplifying the expression, we get:
Wood's volume * (Water's density - Wood's density - Bird's mass) (Intel_06 Comment: I have no idea how he got this one.)
Water's density is about 1000kg/m3, and wood's density is between 400-750kg/m3. Let's just contemplate if the bird is smart enough to find a light enough wood, so we will calculate with 500kg/m3 for this one.
We have: Bird's mass/Wood's volume=500kg/m3
And to simply say it, it is this we will get:
If the bird is 1kg in mass, then
Wood's mass=1/500m3=0.002m3=2dm3
What is the concept of 2dm3? About two regular bricks.
What is the concept of an 1kg bird? Well, the normal hen is 3-4 pounds, it is only a little chick that is 1kg. Can a chick possibly pick up two bricks or an arm-width stick? Even if it could, the wind resistance would blow the two to Atlantic, not Pacific.
The prompt-giver could also say the bird is bigger. Well, bigger birds are heavier! It will then not be two bricks, instead a full-on pillar.
So in conclusion, Science tells us, no matter what bird, none will choose to use a wood branch to travel across the Pacific. If they are destined to do so --- It is a stupid one, one stupid enough to get eaten by fishes drowned in the ocean. For the supposed rationality built upon this story of stupid birds, only stupid birds will believe.
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