[Goto]

I really can't think of a science-related question right now, so whoever fills in the blank word gets the next one.

Aperture _____ : We do what we must, because we can.

[Rylkan]

Since this doesn't seem like a real science question, I full on admit to looking it up. Quotes cannot be deduced.

Aperature Science?

[Goto]

Yep.
I was feeling lazy, and it amused me to have the answer in the Science Trivia topic be 'Science'.

Also, if you didn't know it then you should definitely play Portal. The quote is the first line from the credits song, which is one of the most hilarious things I'd heard in a game in a long time.

[Rylkan]

"Twinkle Twinkle Little Star..."

What causes the twinkling we see when we look at the stars and why?

[Zoo]

Instability in the atmosphere, and starlight is basically a point source. The atmosphere bends/scatters/attenuates light, and different parts have different characteristics (temperature, density, composition, etc.) and will thus bend the light slightly differently from each other, so the interaction of the different layers/air masses and such make the starlight "twinkle".

[Rylkan]

Indeed. Your turn to stump us. (:

[Zoo]

Always feel like someone else is talking when I type answers like that >_<. I wouldn't talk like that. But then the people I generally discuss scientific matters with are either ignorant (that word seems to have taken on a negative connotation...) or 5 years old.


Hmm...


Why is altruism believed to be extremely rare or perhaps even non-existent?

[Rylkan]

Hard to Answer that. Seems much more philosophical.

So to be corny, I will say "Because Chivalry is Dead."

[Zoo]

Heheh... nope, it's nothing at all to do with philosophy

[Goto]

Well this is a science trivia, so it'll be relating back to biology I guess.

My guess would be because altruism is not a good survival trait, a "survival of the fittest" approach towards evolution relies on organisms being selfish. Although a community structure can be beneficial to survival for the many, true altruism is putting someone else ahead of you with no possible gain for yourself, and thus the capacity for this would tend to be weeded out (if it was genetic, anyway).

Umm.. Yeah, I don't actually know any biology or genetics, so that's my guess.

[Zoo]

Yep. Most, if not all, cases of 'altruism' in nature (people are often a special case... our social structure, adaptability, etc. make it possible for us to possibly do things that wouldn't be evolutionarily beneficial) are actually examples of indirect fitness, where the organism, even if it isn't producing its own offspring, it's still preserving at least some of its own genes.

One example is Florida scrub jays; the offspring from one year help raise their brothers and/or sisters the next year, when they could be raising their own young. At first glance it's "awww, how cute!" or whatever, but looking closer there are factors that make it harder for a one-year-old jay to reproduce -- successfully securing territory is difficult being on the 'small' side, and not being a well-established pair doesn't help, and so on.

Alarm calls are another one. I think it's prairie dogs we learned about; they're much more likely to give an alarm call if their siblings are nearby than if other less-related individuals are.


Anyway, your turn, and make sure you post a question this time

[Goto]

... Yes, miss.

Gah, having a lot of trouble thinking of a question. I went to wiki to help, just ended up getting sidetracked reading stuff.
I've been at it for like half an hour, so I'll just post something off the top of my head so you people will stop hounding me to think.

A positively charged particle is moving through a uniform magnetic field. What should the angle between the particle's velocity and the field be to maximize the increase of speed of the particle?

[Rylkan]

Since it is a cross product of the test charges velocity as a vector, and the magnetic field lines as a vector, you cannot create a force (which means a net change in acceleration) within the direction of the particles motion. Do you mean increase in the overall magnitude of the particles velocity then? Or in the direction of motion, which is not possible.

[Ratty]

So.. looking for the largest force, and since it's a cross product, it's just the vectors multiplied together and then multiplied by sin(theta). Max of sin(theta) is when theta is 90 degrees.

So max increase in speed is when the field is perpendicular to the initial movement.

I guess.

[Goto]

Rylkan got it, it was a trick question. A magnetic field acting on a charged particle can only influence the direction of its velocity, not the magnitude.