Calculating Aerodynamic Drag on Titanic Slowing to 5 Knots

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Discussion Overview

The discussion revolves around the hypothetical scenario of calculating the aerodynamic drag on the Titanic as it slows from 25 knots to 5 knots, particularly focusing on the influence of a woman mimicking a scene from a movie by stretching her arms at the front of the ship. The conversation touches on various aspects of drag, assumptions about the scenario, and humorous takes on the situation.

Discussion Character

  • Exploratory
  • Debate/contested
  • Conceptual clarification

Main Points Raised

  • One participant humorously suggests that the Titanic would come to an abrupt stop at the seabed long before the woman could slow it down.
  • Another participant calculates the drag force based on a typical person and estimates the distance required to slow the Titanic, noting that this calculation assumes constant drag and acceleration.
  • Several participants express skepticism about the adequacy of the information provided, questioning various details about the woman’s attire and physical characteristics that could affect the drag.
  • There are humorous speculations about the extreme deceleration potentially causing the woman to fall overboard.
  • One participant suggests that positioning the woman as a human sail could counteract drag effects, presenting a whimsical alternative scenario.
  • A later reply introduces a psychological angle, suggesting that the ship's captain would order a stop to save the woman, implying a narrative twist.
  • Another participant provides a brief, seemingly arbitrary answer of "4," which lacks context or explanation.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the calculations or the implications of the scenario. Multiple competing views and humorous takes remain throughout the discussion.

Contextual Notes

The discussion includes various assumptions and lacks definitive information regarding the woman's characteristics and the conditions affecting the drag calculations. The humorous nature of the conversation leads to speculative and non-technical contributions that complicate the analysis.

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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 [tex]C_D A = 9 ft^2[/tex], 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 [tex]4.11 x 10^7 m = 2.56 x 10^4 miles[/tex]
 
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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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