On How To Decide What People in a Culture Should Know

[lhynard]

Last night, I began co-teaching a course on chemistry for science teachers. The other teacher showed a video about the American science education system and problems with it. Our students were also given a test on common chemistry misconceptions. I was amazed at how poorly both the ones interviewed in the video -- Harvard graduates, even -- and

Comments

[dogs_n_rodents]

I took a wild guess with the mass of the tree. I presume that water makes up the majority of the cellular mass of tree, and given it's more dense than any of the gases... Then again, my biology is rusty.

Although it surprises me how many people probably presume the greater volume = greater boiling point. Really, it shouldn't, given the undergraduates I've taught who definitely tell me that our education system isn't perfect...

[lhynard]

I actually should have said log instead of tree, as in dry weight. When the tree is alive, water is constantly flowing through it, and the mass of the tree will depend very much on when the last time it rained was.

The actual interview question to Harvard grads was:

"Here is a seed and a log. How did the seed gain so much mass to become the log you are now holding?"

Almost everyone said, "From light, from water, and from minerals in the soil."

Then the interviewer said, "What would you say if I told you the bulk of the weight came from carbon dioxide?"

Most everyone said, "I would have trouble believing that."

"Why?"

"Because air doesn't have weight!"

But of course, air has tons of weight. And minerals make up a negligable amount of tree mass. Light makes up none, because light does not have mass.

The formula of photsynthesis is:

Water and carbon dioxide catalysed by light gives glucose and oxygen.

Glucose is then converted into almost everything else the tree ever needs.

[bpr]

While I recognized that the water is the same temperature, I was uncertain as to whether the therometer would read the same. For example, would one be more exposed to cooler air? Overthinking to defend against the "trick question".

As for the tree, I recognized that CO2 (btw, it appears you mispelled dioxide) would contribute, but I applied my knowledge of biology that the majority of my weight it H2O to estimate a similar finding for a tree. A log would have been different.

[lhynard]

Yeah, unfortunately the text of polls is uneditable. You are right that a "log" would be different. Hence, my edit above. Thanks also for the spelling correction z and x are next to each other on the keyboard.

[jeltzz]

I should have read the question before answering it.

Recently Australia introduced a *stupid* citizenship test, asking questions that it thinks citizens should know - including sporting trivia. I don't think sporting knowledge should be part of what people need to know.

[earthminor]

Yay smarter than you!

[jeltzz]

more attentive perhaps, but not to your job apparently.

[lhynard]

Hey! No marital spats on my blog!

(Silly Newlyweds, *sigh*)

[nikkijeanne04]

How long has the tree been a log? And where has the log been laying? Has it been laying in a moist rainforest or is it petrified?

[lhynard]

I don't know!

The question is meant to be asking for dry weight.