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Old 04-17-2017, 02:27 PM   #161
ed17331
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Bump. I'm in jury duty this week and bored AF.
While you are waiting
You should try writing Haiku
To occupy mind
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Old 04-17-2017, 02:30 PM   #162
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While you are waiting
You should try writing Haiku
To occupy mind
You should have went in

But decided to skip it

Prepare your anus
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Old 04-17-2017, 03:02 PM   #163
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Oh god, I didn't actually expect a real technical question. Figured it would be the usual amount of trolling and BS...guess it figures that it's you who's asking this though lol.

Anyway, a "sonic boom" is somewhat a misnomer as it's generated by the compression of fluid (air) in front of an object traveling at that speed. It's the point where you switch from linear to non-linear in terms of material properties. I'm sure you know this already (if you didn't, I'd be concerned) but the speed of sound in a liquid or solid is obviously different than through air. Also, the effects of such are very different.

Ok with that said, lets take water as an example since it's something most people will understand. If you have an object fast moving through water (lets assume still water), you can get to the non-linear portion of the curve very fast because of the nature of the fluid so the speed that you'd need to reach that isn't equal to the speed of sound. Also, because this characteristic is relative motion, not absolute, you can get an even lower speed if you have fast flow in the opposing direction.

To answer your question, you will still get a similar bow shock as you would in air, the physical phenomenon is largely the same but some other interesting things will happen too. As you get to that point, you start getting cavitation starting to occur just behind the bow shock which is the key to a lot of fast underwater travel. For those who are following along at home, cavitation is the outgassing of fluid (it's actually the creation of a void in a medium but for the purposes of this discussion it's outgassing) due to lower local pressure. If you look at videos of bullets or torpedoes in water, you'll see that they are encased in bubbles. This is the cavitation occurring behind the bow show. The big benefit of this is the SUBSTANTIAL reduction in skin drag force as only the front of the nose cone is subject to drag from the fluid while the rest of the body rides in the bubbles (outgassing) created by the cavitation. As a result, once an object expends energy to get to that speed, the amount of energy to sustain that speed reduces. You also see this in high speed propellers and other such things too.
I've read that the transition to supersonic flow is a singularity in the equations, but I had never heard that about switching from linear to nonlinear; that's really cool.
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Old 04-17-2017, 03:07 PM   #164
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O hey guys.
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Old 04-17-2017, 03:12 PM   #165
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O hey guys.
Oh hey there Sean C

Would you mind sending me nudes?

Don't play hard to get
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Old 04-17-2017, 04:00 PM   #166
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Morgan makes me laugh
With hilarious haikus
That Ninja has skills
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Old 04-17-2017, 04:40 PM   #167
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Oh hey there Sean C

Would you mind sending me nudes?

Don't play hard to get
check pm
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Old 04-17-2017, 05:02 PM   #168
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While you are waiting
You should try writing Haiku
To occupy mind
I got picked as an alternate. Haven't gone through screening yet so we'll see what happens. There are a few paralegals and one attorney that are going through screening that will be promptly dismissed so I'm guessing I'll be next lol.
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Old 04-17-2017, 06:02 PM   #169
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check pm
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Old 04-17-2017, 07:33 PM   #170
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I got picked as an alternate. Haven't gone through screening yet so we'll see what happens. There are a few paralegals and one attorney that are going through screening that will be promptly dismissed so I'm guessing I'll be next lol.
Prediction for you:
They will waste tons of your time
Then tell you "go home"
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Old 04-28-2017, 09:22 AM   #171
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How do we create and maintain a magnetosphere around Mars so that a thicker atmosphere can be retained on a long term basis?

Solution must be practical and cost effective.

Show your work.

You have 20 minutes.

Go!
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Old 04-28-2017, 09:29 AM   #172
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Prediction for you:
They will waste tons of your time
Then tell you "go home"
This prediction was 100% true.

Quote:
Originally Posted by ed17331 View Post
How do we create and maintain a magnetosphere around Mars so that a thicker atmosphere can be retained on a long term basis?

Solution must be practical and cost effective.

Show your work.

You have 20 minutes.

Go!
Sounds like the FE exam...

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