Calculating the Probability of Hitting a Spinning Fan with a Dart

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Discussion Overview

The discussion revolves around calculating the probability of hitting a spinning ceiling fan with a dart. Participants explore the theoretical framework and variables involved in the problem, including the geometry of the fan blades and the dynamics of the dart's motion.

Discussion Character

  • Exploratory
  • Mathematical reasoning

Main Points Raised

  • One participant proposes a method to calculate the probability by determining how long the dart takes to pass through the fan and how far the fan rotates in that time.
  • Another participant notes the need for clarity on the shape of the blades and suggests defining the probability distribution for where the dart is thrown.
  • A participant provides specific measurements for the fan blades and the radius from which the dart is thrown, indicating the need for additional definitions for angular velocity.
  • A humorous anecdote is shared about a dart-related injury, highlighting the potential dangers of the scenario being discussed.

Areas of Agreement / Disagreement

Participants express varying degrees of understanding and propose different approaches to the problem, indicating that there is no consensus on the method or assumptions needed to calculate the probability.

Contextual Notes

Participants have not fully defined all variables, particularly angular velocity, and there are unresolved questions regarding the shape of the blades and the probability distribution of dart throws.

Char. Limit
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Here's a question that I thought up while shooting darts through a five-bladed ceiling fan. I'm lazy, so I'll use symbols for the constants in the equation.

Say I have a five-bladed fan of radius R, with a blade width W, spinning at angular velocity V. I shoot a dart of length L through the fan at a speed S. What is the probability that I hit the fan?

Just do the equation, I'll fill in the measured constants later.
 
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Hi Char. Limit! :smile:

Calculate how long it takes the dart to pass through the fan, and how far round the fan goes in that time. Then subtract that distance from the distance between the blades. :wink:
 
Awesome problem. But there's something missing here. It looks like the blades are rectangular. So...we either need to specify some definite radius at which you throw the dart, or define precisely the probability distribution determining where in the circle you are likely to throw the dart.

Let's see what you come up with, mr./mrs. char!
 
The blades are about two feet long, and the radius of fire is about 1.5 feet.

And it's Mr. for future reference (learn something new every day.)
 
Ok, thanks. Just two questions: what do the omega and the little v represent? I've measured the other three (W=5.25 in, R=24 in, and L=3 in). Now I just need those two.
 
Man checks into hospital with dart buried up to hilt in forehead. Sez victim: "Who knew a ricochet could pack so much energy?" News at 11.
 

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