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Spoon Riddle!
🕑 Added 2020-02-07 20:00:53 +0000 UTCHey PG Patrons!
One of my upcoming videos is a riddle, and I wanted to throw it to you guys first. I’d love to include some of your answers in a video too, if you’re interested! Check the link at the bottom of the post.
Here’s the riddle: If you look at your reflection in the food-side—the concave side—of a spoon, it’s flipped upside down. If you look at the back side—the convex side—your reflection is right-side up.
(Have I lost you yet? I found out recently this was news to some people so, yay cool!)
The riddle I’m proposing takes all this reflecting a step further:
Imagine you could take this spoon with the soup (concave) side facing you, push it through until it’s now a convex surface facing you. Almost like you’re pushing one of those toy poppers (Google “toy popper”)… So at some point, halfway between, it’s going to be a flat surface, just like a mirror and then you keep pushing it and it becomes curved toward you.
Now - obviously at some point, your image has to flip. So the riddle is, how does your image flip? Do you rotate clockwise, do you shrink really small and then get bigger? Do you get really big and disappear into nothing? What happens?
That’s the riddle. In short: how does your image flip when you take a concave surface, warp it through being flat, all the way to a convex surface?
You can submit your video answer through this form: https://forms.gle/BxrXaNQ1BmxUvv4m6 I'll even choose a few to include in my upcoming video!
Comments
Olaf Doschke
I was thinking of the convex mirrors sometimes available in parking lots (see Twitter replies on your palm tree drops post) and of concave mirrors like cosmetic mirrors or paraboloid mirrors used in headlights. I came to the conclusion the image should blow up when you start concave and flatten it, as you move the focus out. I did get to the conclusion this blows up and then comes back and shrinks, but there's that moment when the mirror would be flat and not magnify or shrink the image. I didn't get the idea of how this actually is about two images, the real and virtual mirror image. The essentail moment is even before the mirror becomes flat, as I realize now. I did a bit of raytracing, but it looked wrong and I didn't finish it. flattening a paraboloid just magnified a bitmap and didn't distorted it in any way, when you look straight on through the focal point, so it was quite a surprise that this actually looked this way with Derek's paraboloid mirror when you just moved away.
Brian O'Connell
I will defend this to the death. I don't care how wrong it is
Brian O'Connell
Fun fact.... the proper way to stir your coffee or other drink with a spoon is to put your thumb in the food part and stir with the skinny part. The spoon is like a holster. You're welcome. :)
