A Few Questions!

[Almst EE Student]

Motive: Set up a (high school) physics exhibit on light.
Criteria: N/A. Let creativity reign.
Goal: What better way to educate than to explain the history.

What I have in mind,

Empedocles: "We see because light streams out of our eyes & touches objects." Maybe I'll toss in him jumping into Mt Etna to prove he was a god

Euclid: "Why do objects further away seem so small in comparison with objects near our eye?" His example: Took his finger, held it up near his eye, & looked out at a pillar in the distance. Then he positioned his finger so it was the same size (height) as the pillar. His solution: The eye, the top of the finger, & the top of the column must lie on the same line, & for that to be true, the rays from the eye must follow straight lines.

^Was Euclid actually correct here, or is this perception?

Then I figured I'd add in the story of Al-Hakm ordering Alhazan to stop the Nile flooding. Alhazan made multiple discoveries upon sitting in confinement. Found that the angle at which light hits an object is the same as it leaves an object. I guess from this, he theorized that all objects reflected light. Oops, I forgot. -Alhazan found it improbable that light "streams" out of our eyes. He questioned this upon looking into the sun & feeling great pain.

^I have no idea why the angle at which light hits an object & is reflected matters here. Story goes, this is what led him to think that all objects reflect light. What if the angle was different by the way? I mean, what if the angle upon which light left an object was different than the angle at which light hits an object?


This is getting lengthy I'd go on to Roger Bacon with color, & end up with Newton & the prism.

Does anyone know any U.S. suppliers where I can pick up a prism? What's the best way to show this? I've asked my teacher if I can set up a laser. I can as long as I keep it within a few mW Don't worry, there are plenty of safety goggles. He just doesn't have any white (forgot the nM) laser modules. I've tried the LPF forums, & have came up w/ nothing. Anyone?



I think it'd be a bit difficult explaing Maxwell's equations, & relativity to most students my age. I do want to introduce C at the least.

I'm looking for suggestions!

Thanks!

[MikeAurelius]

For prisms, try Edmund Scientific.

There is no such thing as a white light laser. White light by definition is "all colors". Laser light by definition is one or a very narrow band of light. Edmund Scientific would also be a source.

[Uncle Fester]

Pick up a copy of this book.

http://www.amazon.com/Discoverers-Da.../dp/0394726251

He has several pages of light, vision and eyeglasses history. (The whole book is a great read!)

I don't know if this would work but when in school we had to create a series of lenses to focus an image about a foot away.

I used a small viewmaster (?) picture negative and with a penlight shinning through made it pass through a series of concave and convex lenses to demonstrate the refractive properties of lenses.

Of course we had to calculate first what lens powers would be needed and placed where. (Hello Mr. Gauss!!!)

[Almst EE Student]

There is no such thing as a white light laser. White light by definition is "all colors"

You got me there