Swans on Tea

Optical Trapping and the Momentum of Light
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The explanation talks about the wave-particle duality, but I think that’s a distraction. This is a dipole force phenomenon; the beam’s intensity is greatest at the center, and where the focal point occurs, as shown in the [...]

Dot Physics has been assimilated by the Borg, but (unsurprisingly) Rhett, through his blood, sweat and tears, continues to post cool stuff. This time, it’s an angular momentum demo and explanation. I’ll post the video here as a teaser; go to the post for the explanation
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Making light rays in the classroom
Laser level as the source, and lenses using gelatin as the medium, to demonstrate Snell’s law.

The Boy Who Harnessed the Wind: Persistence, Jury-Rigging, and Ingenuity Against All Odds
A Malawian youth, whose family could not afford his school tuition, learns some physics and builds a windmill to generate electricity for his village.
William scoured trash bins and junkyards for materials he could use to build his windmill. With only a couple of [...]

There’s a fairly well-known science question which asks
How does the amount of energy per gram of TNT compare with the energy per gram of a chocolate chip cookie?
I’ve discussed before why I think the answer should be, “About the same,” if you’re doing a first-order approximation, and depending on what options you give for [...]

Throwies are simple LED circuits — the LED and a battery, with an optional magnet so they will stick to ferromagnetic materials.
Evil Mad Scientist Laboratories does a pretty exhaustive analysis on the circuits, looking at battery life and potential danger of these simple circuits. Some thoughts on throwies
This data shows a couple of interesting things. [...]

Melt and Blow CD Bubbles
Learn how to blow bubbles with your old plastic CDs in this edition of ‘It’s Effin Science.’

Physics Buzz: How to Build a Spectrometer with Just Three Household Items
How to build a cereal box spectrometer.

Dot Physics: A demo for the color black
What do you see when you are in a completely dark room with no lights?

Is coming from sciencegeekgirl’s Hands on Science Sunday: Feeling pressured?
All you need is a big trash bag and an industrial strength vacuum cleaner, and a willing victim (er, “faithful subject of science.”) The victim (aka “subject) gets inside the bag, and once you suck all the air out of the bag with the vacuum cleaner, [...]

Those who divide the people in the world into two types, and those who don’t.
Or, you can divide experiments up by classifying them as edible or inedible: Edible/Inedible Experiments Archive

17 cool magnet tricks
I’ve done several of these, including a version of the homopolar motor. The eddy current damping is fun, too — you can make nonmagnetic metals react to magnets by inducing current flow in them. Lenz’s law.