Category Archives: [PhysicalScience]

Friday Sprog Blogging: Kids Day at SLAC 2010 and magnets.

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The younger Free-Ride offspring continues recapping Kids Day @ SLAC 2010 with a report on another workshop:

Dr. Free-Ride: Tell me about the magnets at Kids Day.

Younger offspring: Well, the magnets … first we got to make our own magnets, and we had a piece of steel or something — a bar of steel. We wrapped a lot of wire around it; the two ends were sticking out. We also got a battery with it, with two chicken clips.

Dr. Free-Ride: OK. We used to call them alligator clips, but I understand that reptiles and birds have a common ancestor, so chicken clips works.

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Friday Sprog Blogging: Kids Day at SLAC 2010 and the saga of Mr. Marshmallow Man.

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The younger Free-Ride offspring reports on one of the workshops at Kids Day @ SLAC 2010:

Dr. Free-Ride: Tell me the story with Mr. Marshmallow Man.

Mr. Marshmallow Man

Younger offspring: Mr. Marshmallow Man got put into a vacuum chamber, and it was also kind of like a time machine, ’cause when they put him in, he was, like, porking out on all these marshmallows. Except, he wasn’t eating himself. And then, the time flew fast and he turned eighty. Then he porked out some more. And then, time flew more fast, and then he turned a hundred, and then his head fell off and I came to his funeral. (In a dramatically sad voice) I’ll never forget you, Mr. Marshmallow Man!

Dr. Free-Ride: OK, but can you tell me what was happening in terms of the balloon in the vacuum? What actually happened?

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Friday Sprog Blogging: Kids Day at SLAC 2010 hazards and mitigations.

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Longtime friend of the Free-Rides LO has been instrumental in hooking the Free-Ride offspring up with Kids Day @ SLAC. Finally the year has come when the younger Free-Ride offspring meets the age requirements to join the elder Free-Ride offspring. As is our practice, we prepared by reviewing the safety information:

Dr. Free-Ride: So, we’re talking about Kids Day @ SLAC. I’m showing you the logo for this year’s Kids Day @ SLAC. There seems to be some sort of — I don’t know if that’s a laser beam or something. Looks interesting. But, the part we need to discuss has to do with the safety information. “All children must wear long pants, Kids Day T-shirts” — which you guys will get from LO and put on when you get there — “closed-toe shoes, no jewelry, and long hair must be pulled back. Please review the hazards and mitigation information on the workshops.” Younger offspring, let’s look at workshop B.

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Practical chemical engineering.

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It’s day two of my training course, and as I contemplate my mug of decaf, I am suddenly flashing back to a question that was rumored to be part of the chemical engineering qualifying exam in my chemistry graduate program. As it’s an intriguing problem, I thought I’d share it here:

In the dead of winter, a professor sends his grad student out into the cold to fetch him a hot beverage from the cafe. “Coffee with two creams, and make sure it’s HOT when it gets to me!” the professor barks.

Shivering from fear as much as cold, the grad student procures a 12-ounce styrofoam cup of hot coffee and two little containers (maybe 20 mL each) of half and half at the cafe. To maximize the temperature of the coffee when it is delivered to the prof, should he add the half and half to the coffee before he walks it through the cold or after?

Feel free to work together on this problem, and please show your work in the comments.