Saturday, February 27, 2010

How to start a brawl at the Physics Bar, Method #7

Refer to the changes in the speed and wavelength of a wave passing from one medium to another as "refraction."

And if you don't know why that will cause a brawl, you have no business in the Physics Bar!

Thursday, February 25, 2010

What kind of circuit is this?

I'm not sure what to call the circuit involving the chain of uninsulated Brainiacs in this clip. See 2:13-4:00.



Your ideas?

The segment from 4:00-4:53 is a nice example of a series circuit!

UPDATE: Commenters and NCNAAPT/PTSOS list responders have identified this as a resistance ladder or R-2R network. I love having access to the brainiacs of cyberspace!

Sunday, February 21, 2010

Torque on ice

Gunn High School physics teacher (and President of the NCNAAPT), Claudia Winkler, likes this "Physics at the Olympics"... moment!

Take a look:

Wednesday, February 17, 2010

Why does Glenn Beck hate science?

Glenn Beck recently trashed Bill Nye the Science Guy. Nye's crime? Other than being involved in science? An appearance on The Rachel Maddow Show. To make matters worse, Nye spoke truth about snowstorms and global warming. Clearly, Nye was begging to be put on Beck's Enemies List.

While Beck attempted to sell his typical twisted manipulations, Maddow wasn't buying. See for yourself.

Visit msnbc.com for breaking news, world news, and news about the economy

Tuesday, February 16, 2010

Check 2: Still no new RTQs

The 2010 RTQ release can no longer beat those of 2006, 2007, or 2008. If they drop before February 25, they can still beat 2009.

Raise your hand if you think that's going to happen.

That's what I thought.

See Check 1 for more.

Saturday, February 13, 2010

Adiabatic cooling puzzle

I'm a big fan of the PhET simulations.

But I'm puzzled by one aspect of the "Gas Properties" simulation.


If you open the simulation and squirt some gas (maybe 100 particles) into the chamber, the particles bounce around nicely. If you then compress the gas, the pressure and temperature increase as one might expect.

But reset it, squirt some gas in, and expand the chamber. The pressure drops, but the temperature remains the same. I was hoping for adiabatic cooling, but all I got was isothermal (and adiabatic!) expansion.

My thoughts? I want the temperature to drop: particles bouncing off a receding wall should recoil with reduced speed. And an expansion shouldn't be isothermal unless heat is added.

The good people at PhET assure me this is what's supposed to happen. But sometimes I'm just too thick to get it.

Educate me, experts!

Tuesday, February 02, 2010

Vaccine-autism link is dishonest and irresponsible

And so the rug is pulled out from beneath the feet of doctor-not, Jenny McCarthy.

Science wins once again. An errant claim that went out into the world failed the test of reproducibility. Sadly the errant claim, connecting vaccination with autism, collected fans. The fans are not burdened with knowledge of or adherence to the methods of science.

The fans trust a Playboy playmate's "wisdom" over the consensus of the medical community. They will, no doubt, have a continuing negative effect on health care for years to come.

See The Jenny McCarthy Body Count and Science Based Medicine for more.