Wow! Who ever would have thought that a massive ball of continuous nuclear fusion hundreds of thousands the mass of the entire Earth and pumping out 384,600,000,000,000,000,000,000,000 watts every single second...could be dangerous?
I love Portland, and the entire area is beautiful, but it really is second only to Denver as the country's most boring, unremarkable big city. There isn't even anything inside the snow globe that would make one think, "Oh, hey! Portland!"
That happened with a lighthouse down in Florida, the sun shining through the Fresnel lens was setting brush fires, so they had to put up a metal barrier on the landward side of the lens.
The focal length of a spherical lens, where it's literally a complete sphere, would be so short that the focus would actually be within the sphere. And then you'd also have spherical aberration, that's normally compensated for by having two large-radius spherical surfaces opposing one another, where they're very close to one another, not two halves of the same sphere. With a complete sphere you wouldn't even have a single focus, even within the sphere.
Pure bullshit, unpossible.
This guy fell asleep on his couch smoking a j, and doesn't want to admit to it.
Hagar: Not quite. A prism reflects, and ideally won't expand significantly (a notional "perfect" prism wouldn't at all).
(With the caveat that unless it's in a system of them designed to counter it, it will disperse mixed wavelengths relative to one-another in a beam of mixed light; but any one-color beam of light won't be dispersed.)
A lens can concentrate OR diffuse rays, depending on its design.
Pastafarian, that's a good point, but I think you missed something. It's been a while since I studied optics, but I think the water in the globe will lessen the angle of refraction (the light refracts twice as it enters the globe) so the focal point may very well be outside the globe.
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20 comments:
Prism Power!
Global warming.
Prisms refracts and expands the sun's rays; lenses concentrates them.
The Tierra del Fuego snow globe was questioned but has a solid alibi.
And it would have gotten away with it, too, if it wasn't for those meddling smoke alarms!
This shows the wisdom of the TSA confiscating dangerous snow globes that have pyromaniac tendencies.
"If you put it on the end of a staff, it will show you where the Ark of the Covenent is hidden..."
Maybe your staff. Mine is too long.
Wow! Who ever would have thought that a massive ball of continuous nuclear fusion hundreds of thousands the mass of the entire Earth and pumping out 384,600,000,000,000,000,000,000,000 watts every single second...could be dangerous?
I love Portland, and the entire area is beautiful, but it really is second only to Denver as the country's most boring, unremarkable big city. There isn't even anything inside the snow globe that would make one think, "Oh, hey! Portland!"
That happened with a lighthouse down in Florida, the sun shining through the Fresnel lens was setting brush fires, so they had to put up a metal barrier on the landward side of the lens.
Not unlike what happened to the Cosbys' sofa when young Bill turned on "Lights Out".
There isn't even anything inside the snow globe that would make one think, "Oh, hey! Portland!"
Least of all, snow. Portland averages -- what -- 6 inches per winter?
Fortunate he had working smoke alarms and alert neighbors. He seems to have a nice attitude, too. Cute story.
We used to set things on fire with magnifying glasses when we were little kids. And pop ants, which is really sick, come to think of it.
OK, I'm calling bullshit on this.
The focal length of a spherical lens, where it's literally a complete sphere, would be so short that the focus would actually be within the sphere. And then you'd also have spherical aberration, that's normally compensated for by having two large-radius spherical surfaces opposing one another, where they're very close to one another, not two halves of the same sphere. With a complete sphere you wouldn't even have a single focus, even within the sphere.
Pure bullshit, unpossible.
This guy fell asleep on his couch smoking a j, and doesn't want to admit to it.
Well, that's settled. Shit.
Hagar: Not quite. A prism reflects, and ideally won't expand significantly (a notional "perfect" prism wouldn't at all).
(With the caveat that unless it's in a system of them designed to counter it, it will disperse mixed wavelengths relative to one-another in a beam of mixed light; but any one-color beam of light won't be dispersed.)
A lens can concentrate OR diffuse rays, depending on its design.
Coketown: It's not Portland that's boring, it's that snowglobe's bad design (seriously, what amateur did that?).
(That said, I'd recognize it anyway - the KOIN Center is distinctive even when badly rendered.
Me, I'd have picked the St. Johns Bridge, or as a fallback, the Fremont.)
I was never able to set fire to a couch even with a real magnifying glass.
"The city of Portland snow globe tried to burn my house down."
Hate Crime!!!
The sun stayed out in Portland in March long enough to set something on fire? That's the real news story.
Pastafarian, that's a good point, but I think you missed something. It's been a while since I studied optics, but I think the water in the globe will lessen the angle of refraction (the light refracts twice as it enters the globe) so the focal point may very well be outside the globe.
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