Calculating Aerodynamic Drag on Titanic Slowing to 5 Knots

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The discussion centers around a hypothetical scenario involving the Titanic cruising at 25 knots while a woman in her 50s mimics a scene from the movie by stretching her arms at the front of the ship. Participants debate the impact of aerodynamic drag from her flapping arms on the Titanic's speed. One contributor calculates that the drag force would be approximately 19 pounds, leading to a theoretical distance of over 25,000 miles for the ship to slow down to 5 knots, assuming constant drag and acceleration. The conversation humorously highlights the lack of real-world context in such problems, questioning details like the woman's attire and dinner. Participants also speculate about the potential for extreme deceleration to affect the woman’s stability. The thread concludes with a light-hearted take on the scenario, suggesting that the captain might order a stop to save her, humorously implying that the ship's drag coefficient could play a role in the outcome.
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The Titanic is cruising at 25 knots in a no-wind condition. A typical woman in her 50's duplicates the scene from the movie where she stretches out her arms at the front of the boat.

Due to the extreme aerodynamic drag from the woman's flapping arms, how long will it take to slow the Titanic to 5 knots?
 
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I think the vessel will come to an abrupt stop at the bottom of the sea bed, way before the woman can slow it down to 5 knots ( even if she started from Belfast :D )
 
Are you kidding? Extreme aerodynamic drag?

At the worst case, with an average standing person relating to a C_D A = 9 ft^2, that results in a Drag force of about 19 Lbf at 25 kts.

The titanic was 46,328 tons. Doing a cheesy F=ma and assuming that drag and acceleration were constant (which they wouldn't be) that works out to a distance of approximately 4.11 x 10^7 m = 2.56 x 10^4 miles
 
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Jeff Reid said:
The Titanic is cruising at 25 knots in a no-wind condition. A typical woman in her 50's duplicates the scene from the movie where she stretches out her arms at the front of the boat.

Due to the extreme aerodynamic drag from the woman's flapping arms, how long will it take to slow the Titanic to 5 knots?
Obviously not enough information:

what did the woman eat for dinner?

Was it a floral print dress? Woven or knit? Cotton, silk, wool, etc?

Earings: diamond studs, gold hoops? What?

That's the thing I hate most about these elementary problems; they fail to take real world singificance into account!
 
Chi Meson said:
Obviously not enough information:

what did the woman eat for dinner?

Was it a floral print dress? Woven or knit? Cotton, silk, wool, etc?

Earings: diamond studs, gold hoops? What?

That's the thing I hate most about these elementary problems; they fail to take real world singificance into account!
:smile:

I'm pleased to see Fred step up to the plate and take this problem seriously, as any engineer should. :smile:

The Titanic is cruising at 25 knots in a no-wind condition. A typical woman in her 50's duplicates the scene from the movie where she stretches out her arms at the front of the boat.

Due to the extreme aerodynamic drag from the woman's flapping arms, how long will it take to slow the Titanic to 5 knots?
With or without full speed ahead? :smile:

Typical woman of what era?
 
Jeff Reid said:
The Titanic is cruising at 25 knots in a no-wind condition. A typical woman in her 50's duplicates the scene from the movie where she stretches out her arms at the front of the boat.

Due to the extreme aerodynamic drag from the woman's flapping arms, how long will it take to slow the Titanic to 5 knots?
Couple seconds, tops!

But the more interesting question is will the extreme deceleration spill the woman into the soup?
 
Gokul43201 said:
But the more interesting question is will the extreme deceleration spill the woman into the soup?
I bet she is wearing ultra high traction deck loafers and support hose with high elastic modulus in the longitudinal direction. :biggrin:
 
Obviously not enough information

Sorry, here's a link to a pic, the one with the cup holder and the cool hat. Is this what the members of the sisterhood will look like in 30 years?

http://jeffareid.net/misc/bamafans.jpg

To help recover from that pic of a couple of typical older women, a cute pic of our doggy:

phoebe05.jpg
 
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Jeff Reid said:
Sorry, here's a link to a pic, the one with the cup holder and the cool hat. Is this what the members of the sisterhood will look like in 30 years?

http://jeffareid.net/misc/bamafans.jpg
:smile: :smile: :smile: :smile: :smile: :smile: :cry: :smile: :smile:
 
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  • #10
Any drag effects could be countered by positioning her atop the funnel arms akimbo again, and letting here act as a human sail, with a good tail wind maybe the Titanic could of avoided disaster by seconds. Why did no one think of this? It's shocking! The unsinkable ship could of winked at God, and our Empire would have remained obscenely proud of her, till we cut her up and used her for tanks during the second world war at least, see! No ones thinking of the damage such a sinking did to our economy, all anybodies thinking about is the drag effect of the crone. Tragiclly shortsighted!

This is a minimum information puzzle btw no ones mentioned if she was smoking a pipe, how on Earth are we suposed to work anything out from that!:rolleyes::wink:
 
  • #11
This is a really a psych question.

5 minutes for the ship's drag coefficient to slow it down...

-because the ships Captain ordered "All Stop", so he can rush down
to save the apparently suicidal lady.
 
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  • #12
The answer is 4
 
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