Today I Learned

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Can a rod that passes through only one hole of a double torus be made to pass through both, without tearing or merging? A fun topology puzzle 😁:

 
Ibix said:
I take it you are familiar with the correct way to slice a bagel?

I've been enlightened; I've been doing it wrong my whole life! Though I'm not sure I quite buy this part :wink::
"You can toast them in a toaster oven while linked together"
But it sure beats this thing of nightmares...:

Line drawing of a dog shaped like an oval sphere with hair strokes showing a parting along its back and another along its stomach, with a face with eyes, nose and open mouth with teeth at the front.


I can feel it staring into my soul o_O
 
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etotheipi said:
Though I'm not sure I quite buy this part
A toaster oven is basically a standalone grill (not what we Brits would call a toaster, if that's what you are thinking of), and I can confirm that you can toast the linked halves in a grill. It's a faff, as is spreading anything on the bagel to eat, but I did it a couple of times years ago for nerd-cred. Use low heat and keep the bagels as far from the flame/element as possible - they don't lie flat and the raised bits tend to burn.

The spherical dog is somewhat horrific.
 
Ah okay, that makes more sense. I can't cook to save my life, though I can at least say that I've gotten pretty good at microwaving. Who knows, maybe I'll branch out and learn how to grill bagels before uni :wink:. Although I'd probably just end up absolutely scorching them...
 
Ibix said:
The spherical dog is somewhat horrific.
Physicists are more accustomed to:
Cartoon 3D render of a small white cow with brown ears, pink snout, and grey spots on its body, standing on grey hooves against a pale background.
 
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Ibix said:
The spherical dog is somewhat horrific.
Reminds me of a puffer fish:
Underwater photo of a puffer fish inflated into a near-spherical shape, with a brown skin covered in pale white dots and small spines, against a blue water background.
 
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Reminded by the trench run computer above, from Diary of a Crazed Mimbanite:

Red 5, your targetting computer's off!

It's ok - the voices in my head told me to do that.
 
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Ibix said:
Red 5, your targetting computer's off!

It's ok - the voices in my head told me to do that.

It's okay! The entire rebellion on Yavin IV is about to be blown to pieces by a huge planet-killing superlaser, but some robe-wearing hermit who I've known for like 3 or 4 days at best tells me things will be just fine if I completely fluke this one-in-a-million shot into a foot wide thermal exhaust port!
 
TIL that womp rats are 2 meters in size while exhaust ports are only 1 foot.
 
jbriggs444 said:
TIL that womp rats are 2 meters in size while exhaust ports are only 1 foot.

My bad, you're quite right! I just eyeballed (guessed...) the figure.

Galen Erso sure wasn't taking any chances!
 
TIL

There is a craze in Saudi Arabia called sidewalk skiing which involves driving on two wheels of a car either drivers or passenger side.
 
Keith_McClary said:

I recognize the blue ones and grey ones from my childhood. :smile:
Ah, Lego Space. But I liked Lego Technics even more; I remember building an AT-AT that could walk (it had a motor). And I also remember me and my friend shooting at the AT-AT with an air rifle. :biggrin:
 
Today I learned that "optimism is just a lack of experience". :smile:
(I read it somewhere on the net and had a laugh)
 
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DennisN said:
Today I learned that "optimism is just a lack of experience". :smile:
(I read it somewhere on the net and had a laugh)
I have heard it from a German stand-up comedian, who called it "lack of information".
 
Today I learned that Freddie Mercury spent much of his childhood and teenage in India.
 
Adesh said:
Which one do you own?
I had a car that came with a starting crank.

Edit: It was of this era


but not a spiffy sports car.
 
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Keith_McClary said:
I had a car that came with a starting crank.

Edit: It was of this era


but not a spiffy sports car.

Obviously not someone that has often done that! The OPs grip on the crank can lead to a broken thumb (at least).

It is safer to place the thumb next to the Index finger, on the same side of the crank handle. An engine will sometimes kick back, fire before reaching TDC (Top Dead Center) when cranking. With the demonstrated grip, the full force of that is taken by the thumb, trying to remove same from hand. Ouch!
 
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Tom.G said:
Obviously not someone that has often done that! The OPs grip on the crank can lead to a broken thumb (at least).

It is safer to place the thumb next to the Index finger, on the same side of the crank handle. An engine will sometimes kick back, fire before reaching TDC (Top Dead Center) when cranking. With the demonstrated grip, the full force of that is taken by the thumb, trying to remove same from hand. Ouch!
Not to mention his tibia.
 
Today I learned that inequalities are most disloyal things, you see
##0 \leq \sin^4x \leq 1##
##0\leq \cos^4 x \leq 1##
But if you add them the right bound become strict :
##0 \leq \sin^4 x +\cos^4 x \lt 2##
 
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Adesh said:
But if you add them the right bound become strict :
##0 \leq \sin^4 x +\cos^4 x \2##

What do you mean? If ##x \leq 2## and ##y \leq 3## then ##x + y \leq 5##, no? Or have I missed something 🙃
 
etotheipi said:
What do you mean? If ##x \leq 2## and ##y \leq 3## then ##x + y \leq 5##, no? Or have I missed something 🙃
Not true (always, may be true sometimes) for trig functions.
 
Adesh said:
Not true (always, may be true sometimes) for trig functions.

Hmm but if ##A < B## then ##A \leq B## always. It doesn't work the other way around!
 
etotheipi said:
Hmm but if ##A < B## then ##A \leq B## always. It doesn't work the other way around!
##\sin^4 x +\cos^4 x## can never be equal to 2. So, we cannot just blindly add two inequalities.