The Valet in the Rain

[Tom Miller]

Do you get more wet walking or running?

I need someone much smarter than myself to help me once and for all. I was a car valet while in OD school (Folk's Folly Steakhouse in Memphis, TN.....highly recommend it....just don't let them park your car )

The valet's consisted of 3 OD students, an accountant, a pilot, and Fed Ex supervisor and a construction contractor (sounds like the beginning of a bad joke).

One particuarly wet, raining evening of car parking one of us came up with a question. Do we get more wet walking to get the car or running to get it? It seems that, while walking, you would spend more time out in the rain but when running, although you would be out in the rain less time, you would run into more drops of rain (assuming a constant, steady rain).

Anybody know which is true? And yes, we had alot of down-time sometimes

 

[Paul Brand]

Tom,

I remember hearing somewhere that you got less wet walking. Don't ask for the reference, but if I remember correctly someone did actually do a study on this.

And you thought you had too much down time

 

[susan resnick]

Good question for "Ask Marilyn" ( Parade magazine section, Sunday papers). I'm no mathemetician, but it seems to me wetness could be measured by the number of drops you were exposed to each second (rate). Assuming a constant volume of rainfall over a defined area, the quicker you passed through a given area, the less wet you would get. I always walk though, because I feel (and look) silly running.

 

[John Tickner]

Try it

I think the answer is that you get wetter the faster you move.

Try cycling in the rain to find out - you will get completely soaked and those that walk will be less wet.

 

[Mike Sirott]

more wet running

There was a Greek god or figure (I forget the name) that claimed to run so fast that through the rain that he didn't get a drop on him.

But I think it would be about the same either running or walking. Think about the factors: while running you would be exposed to more drops per second, because you cover a greater area. While walking you are exposed to fewer drops per second, but are out in the rain longer. However, I think there are more variables. We have to consider one's surface area and dimensions: a person with a larger frontal surface area would collect more drops as they moved, and less, as they stood still or walked compared to a person with a large "footprint" i.e. larger area while looking down on them. The larger foot print would collect more drops per minute while standing still or walking, and relatively less drops then the wider person when they were moving. Just a thought.

 

[Ted Kassalow]

rain

As I wear a raincoat and carry an umbrella I never get wet at all no matter how fast or slow I walk.

 

[Clint Hoxie]

Easy one...

If the rain is falling straight down, you must move forward less quickly than a drop can move from your shoulder to your foot.

If you walk, your shoulders and head will get more drops per square inch, because the time in the rain is the only variable for a (relatively) flat surface in the rain. Your front, however, will be exposed to a substantially larger number of drops per square inch if you move through the downward falling drops quickly enough to contact many drops as you move forward. So the variables then become, how much front surface area, how much vertical drop, and how quickly you walk.

Then there's the real clencher. If you splash water up as you run, you expose yourself to a much greater volume of water.

So, in a vertical rain, walking will expose your body to less water, though your head will get wetter.

In anything but a vertical rain, you need to move quicker, because standing still exposes more than half your body surface to falling water. Run if there is wind.

 

[Clint Hoxie]

P.S.

I can quit for the day now that I've answered this important question...

 

[Ken King]

I think you've ALL got too much time on your hands.

But then, come to think of it, look who took time to read all these replies, and then took time to add a reply.

Ho, Hum

 

[Ron Faircloth]

Judging from the patients I saw this morning, it depends on how close the bus stop is to your housing. Just kiddng. That was not politically sensitive. It doesnt' matter if I walk fast or slow, because I use a waterproof hairspray and if that doesn't work, I hold my lens kit from SCO over my head. Ha! Assuming everything is equal except time, you would get more wet walking. This assumes same distance and drops/time/area. Now, if you are running and forget to look down to miss the mud puddle, then the equation gets all screwed up, because now you have to factor in droplets that are bouncing up from the puddle. I always revert back to the prism equation we use so much. It's like Kevin Bacon, everything seems to stem from it.

Ron Faircloth
NC

 

[Christopher Press]

Hi all,

A search on Yahoo! using the terms 'walking running rain wet' reveals thousands of hits on this subject, far too many to investigate.

I looked at a few sites (especially the sites from various universities physics sites, since this is a physics question), but this one from Seattle Times sums it up pretty well, and seems to reach the same conclusion as the others.

Not surprising this question would be of interest to Seattlites, since this is not a trivial question to ask when you live in Seattle!!

http://seattletimes.nwsource.com/html/localnews/134370003_rain23m.html

Chris

 

[Tom Miller]

Well, there you go.

And it took a couple of North Carolina guys to figure it out. Must be something about those North Carolina people.........not enough entertainment perhaps..........hmmmm

 

[James Jordan]

Didn't see this post until now but I did read a study some years ago that said you get 10% wetter by walking compared to running. The rain was controlled so it won't hold water if you're somewhere else.

Jamie