This discussion board is a place to discuss our Daily Challenges and the math and science
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Comments
Eh, but you can blow your own sail with a fan on the boat, and move the boat forward. That can actually work. So, maybe motorboat companies should give this one another look? (??)
@Satvik Golechha
–
Actually, even though photons have no mass, they can still have energy and momentum, so that troll can go forward. But just not very speedily.
@Michael Mendrin
–
no no hold on a second, what about what I said above? light b... wait. is this because space bends and light just follows it and thus light doesnt bend but it bends relative to other space... ?? errrr
Be careful what you state there. Light is affected by gravity (evidence - light curves around a black hole and stars), meaning it interacts with the higgs field - so, it does have some mass.
Massles particles - tachyons -are yet to be discovered. And remember the implications of "massless":
Dam that pic's on point! Ok now we're getting serious:
So, here's what I think (and I think you know): The propeller, displacing the air forward, pushes itself backwards (N3L), which is the same case with the magnet but in a more indirect way. But the aerodynamics work with pressure in complicated ways to actually make this work. Buut... all this jazz compared to the motor boat, which spins a smaller fan under water much more effectively (even having a "push-off" effect that everyone relies on when trying to disprove rocket science), so yeah... Motorboat companies ain't goin bankrupt any time soon.
No, not likely any time soon. However, this does remind me of a real interesting physics problem, which is that it's possible for a cart, fitted with a propeller that connects to the wheels mechanically, to go downwind faster than the wind! Many say this is impossible, but it's been done, the record being almost three times downward wind speed.
@Michael Mendrin
–
Oh lol that's a no brainer for me - I know why sailing upwind is faster, so I can treat the propellers as sails and apply the same principle and BAM! you can go TEN TIMES faster than the wind. But before that your cart will probably fly apart... Lol
@John M.
–
Uh, it's downwind, John. With a sailing boat, going directly downwind, well, it's hard to go faster than the wind itself. Do you know of a way to go faster downwind? In theory, if a sailboat is going as fast as the wind, with the wind directly at it's back, then onboard, one wouldn't feel much of any wind at all in any direction.
But, yes, when tacking, which is going crosswinds, making clever use of sails, re-direction, and keels, one can go faster than the wind itself. Maybe counterintuitive for non-sailors.
Easy Math Editor
This discussion board is a place to discuss our Daily Challenges and the math and science related to those challenges. Explanations are more than just a solution — they should explain the steps and thinking strategies that you used to obtain the solution. Comments should further the discussion of math and science.
When posting on Brilliant:
*italics*or_italics_**bold**or__bold__paragraph 1
paragraph 2
[example link](https://brilliant.org)> This is a quote# I indented these lines # 4 spaces, and now they show # up as a code block. print "hello world"\(...\)or\[...\]to ensure proper formatting.2 \times 32^{34}a_{i-1}\frac{2}{3}\sqrt{2}\sum_{i=1}^3\sin \theta\boxed{123}Comments
Eh, but you can blow your own sail with a fan on the boat, and move the boat forward. That can actually work. So, maybe motorboat companies should give this one another look? (??)
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I have a better idea:
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I was like "Whaat?!", Trolololl!!! Light has no mass, so by conservation of linear momentum, that troll won't go forward. -_-
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Actually, even though photons have no mass, they can still have energy and momentum, so that troll can go forward. But just not very speedily.
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It takes around 10000 bulbs to lift a sock
Yes sir, I kinda' knew that, I was just trying to troll an already trolled troll trolling trollers... :-P
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And I was trying to troll a troll that trolled a trolled troll trolling trollers...
Wait.. WHAT?
still have MOMENTUM? without MASS?!?
uum.... Ok I'm outa here.
no no hold on a second, what about what I said above? light b... wait. is this because space bends and light just follows it and thus light doesnt bend but it bends relative to other space... ?? errrr
"Light has no mass..."
Be careful what you state there. Light is affected by gravity (evidence - light curves around a black hole and stars), meaning it interacts with the higgs field - so, it does have some mass.
Massles particles - tachyons -are yet to be discovered. And remember the implications of "massless":
a=mFnet⇒a=0Fnet⇒a→∞
Dam that pic's on point! Ok now we're getting serious:
So, here's what I think (and I think you know): The propeller, displacing the air forward, pushes itself backwards (N3L), which is the same case with the magnet but in a more indirect way. But the aerodynamics work with pressure in complicated ways to actually make this work. Buut... all this jazz compared to the motor boat, which spins a smaller fan under water much more effectively (even having a "push-off" effect that everyone relies on when trying to disprove rocket science), so yeah... Motorboat companies ain't goin bankrupt any time soon.
Log in to reply
No, not likely any time soon. However, this does remind me of a real interesting physics problem, which is that it's possible for a cart, fitted with a propeller that connects to the wheels mechanically, to go downwind faster than the wind! Many say this is impossible, but it's been done, the record being almost three times downward wind speed.
Log in to reply
Oh lol that's a no brainer for me - I know why sailing upwind is faster, so I can treat the propellers as sails and apply the same principle and BAM! you can go TEN TIMES faster than the wind. But before that your cart will probably fly apart... Lol
Log in to reply
Uh, it's downwind, John. With a sailing boat, going directly downwind, well, it's hard to go faster than the wind itself. Do you know of a way to go faster downwind? In theory, if a sailboat is going as fast as the wind, with the wind directly at it's back, then onboard, one wouldn't feel much of any wind at all in any direction.
But, yes, when tacking, which is going crosswinds, making clever use of sails, re-direction, and keels, one can go faster than the wind itself. Maybe counterintuitive for non-sailors.
How do you know it won't go backward? :P
Water is diamagnetic. So, I think it wont be possible.
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Actually, that's not the reason why. See Conceptual Physics I.
Can you tell now why this won't happen?