Riding in the Rain? Stay Dry Through Speed.

Comments

• 

  Jot

  Feb 23rd, 2010

  Nice thought exercise.

  However, in the last paragraph you state:”[...] the path length, which in turn represents speed.”

  This is obviously incorrect. I could declare a new point B’ that is infinitely close to A. Regardless as to how fast (or slow) you move that math is going to be ugly.

  But let’s move on from geek humor.

  The field of rain is evenly disbursed. At infinite speed, or even something slower like a speed that is fast enough to complete the path before any more drops intersect the path you should hit the minimum.

  After that, it becomes more difficult. Let’s say you move slightly slower, so that new drops are entering your path and you are likely to hit them, plus
  the old drops. That sure seems like a net gain, right?

  But since the field is evenly distributed the new of drops that were above you that enter your plane will also be at the bottom and leave your plane (now lying on the ground so you run over them instead of intersecting them).

  They only way I can see this not to be true is for you to assert that the ones you run over also make you wet.
• 

  chd

  Feb 23rd, 2010

  There are some assumptions that I did not make completely clear in the original description.

  Placing a new point B’ is not allowed; in this diagram, the positions of (A) and (B) (the edges of the graph) represent your start and finish locations, so the horizontal distance between them represents your physical trip length. It is constant for a given analysis.

  We also assume that you travel through the graph at a constant speed. Time is represented by vertical (Y-axis) deflection; you move through the graph at a constant rate, and the (variable) vertical component of your path corresponds to the (variable) speed of physical travel.

  And droplets you run over *do* make you wet. Moving infinitely fast does not keep you dry—title of the original post notwithstanding—it just keeps you minimally wet.

Leave a Comment