# Who gets more wet during rainfall?

Who gets more wet during rainfall, one who is walking or the one who is running? Back your statement with mathematical proofs.

Note by Vishwesh Ramanathan
7 years, 1 month ago

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## Comments

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Simple answer. Assuming that the man is in rain, if he walks or runs for a specified distance to, say the bus stop, he will eventually hit the rain drops falling from his side. Even if he moves faster, he may escape the raindrop, that was bound to fall in the position he was initially, but will get hit by the rain drop, that was bound to come in his final position. But, if he walks, he will spend more time in the rain, hence getting more wet. Also, if he runs, the surface water droplets sticking already will escape at a faster rate. So, he must run. Bottomline: If the above statements increase your factor of confusion, consider another question. What would you do if instead of raining cats and dogs, it rains bullets? You needn't answer

- 7 years, 1 month ago

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That's the correct answer

- 7 years ago

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nice analogy

- 6 years, 11 months ago

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Myth busters ran an interesting experiment on this. You should check it out. Your answers makes logical sense, but the experiment shows otherwise.

- 6 years, 9 months ago

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Watch this video from "MINUTEPHYSICS"...They have derived a very nice formula for the wetness i.e. Wetness = Total amount of rain hitting from top x no. of seconds in rain + amount of rain hitting from the sides x no. of meters run.
http://www.youtube.com/watch?v=3MqYE2UuN24 :)

- 7 years, 1 month ago

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That's exactly what I thought of when I saw this question.

- 7 years, 1 month ago

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Me too!

- 7 years, 1 month ago

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SAME

- 6 years, 11 months ago

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"Wet" has two interpretations - either you want the hero to hit more water (vectors & maths).... or you want water to stick on him (surface tension & physics)..., We'll look at both cases, I make 5 reasonable assumptions to do it.... Ok, here's my attempt.., 1) Suppose all falling rain drops have same direction of velocity, having vertical component V & horizontal component H..., 2) Let our hero/heroine run on the ground (horizontal) with velocity V2, having components along H as h, & perpendicular to it as k..., 3) Now also assume that the droplets at any horizontal plane are uniformly distributed... 4) Also, all the clouds are at same level, meaning the droplets are formed in the same horizontal plane in the sky..., 5) Effects of rotation of earth & centrifugal pseudo force is neglected..., if h=H & k=0, then while motion, the raindrop will fall right on the hero because the relative velocity is vertical, in this case the amount of water hitting him is minimum = [amount of water falling per metre square]*[the projected area of his head & shoulders from the bird's eye view].... Any other "way" of walking or running (whether k may not = 0, or H may not equal H, or both) these will not give an exactly vertical relative velocity, therefore in all other "ways" of walking & running, hero will get more wet..., Now for the physics lovers, assume the same 5 assumptions, plus, consider that the dress of hero is "wet-able" contact angle less than 90, now if the drop hits harder, it will have a more energetic collision, will have more tendency to rebound, its as if, spilling the water on floor by toppling the glass, versus streaming it from the 7th floor, more like how waterfalls work, the falling water, doesnt even wet water, it rebounds largely, from that observation, I infer that when you take h opposite to H & increase k as much as you can, you increase the relative speed, thereby you should get less wet, but remember, now you will also have water hitting you on more area of your body, now it will not only wet your head & shoulders, but also every part which gets illuminated when an areal light would've been falling on you with its normal along the relative velocity, you can optimize it from calculus, simplest case:: by assuming your body to be sphere or radius R & proceeding with the above 6 assumptions

- 7 years, 1 month ago

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but if you hit water with extremely large relative velocities, then it will not wet you, irrespective of how large of a surface area you're having... I inferred this from the "Liedenfrost effect"

- 7 years, 1 month ago

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The man who is running because the man is not only running into the rain, the man is also getting rain on him. If there are 15 rain drops in each 1 foot of space that the man go through, then he is not only getting rain on him, he is also slamming in to rain! The man walking only get the 15 not like five foot man getting 75 drop.

- 7 years, 1 month ago

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One who is walking get more wet bcz able to collect more rain vectors in comparison with the running one if they are moving in the same direction of rain or if the rain is falling vertically downwards but if they r moving in opposite direction than vice versa.

- 7 years, 1 month ago

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at first,we assume that the volume of falling rain in evry meter and every second (or we can name it as the intensity of the rain)is the same and the running people and the walking people are the same

so,the rain we get i(g)s related to our body surface that attach with the rain(s),the volume of falling rain in every second (v)and meter and the time we being in the rain（t）

if a person is walking in the rain mostly only shoulders and head will attach with the rain drops and if a person is running his surface that attach with the rain drop will increase and we assume it is 2times more than a walking person 2S(walk )=S(RUN)

so,we compare the rain gets by walking and running people

walking=sv1t1 running=2sv2t2

v1=v2 so the rain gets by two person is determine by their moving speed,and the velocity of the running person must over 2times more than the walking person so thathe get lesser rain than walking person

- 7 years, 1 month ago

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Umbrella mam

- 7 years, 1 month ago

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I am not sure of the reason, but I think it depends on the volume of $parallelepiped$ covered by a man. If he is moving, more volume is covered meaning more wetness

- 7 years, 1 month ago

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The one who is walking .

- 7 years, 1 month ago

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The man who is running will get more wet.

- 7 years, 1 month ago

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It would depend on how fast he is walking. The slower they walk, the more time it would take to get to your location, which means the one who walks the slowest would get the most rain.

- 7 years, 1 month ago

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one who is running gets more wet.

- 7 years, 1 month ago

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the walker with more vectors added in same direction

- 7 years, 1 month ago

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the real question is what is the type of wind blowing.... iff the air is medium in nature then the rainfall will be vertical..when we walk we try to be straight but when we run simply we try to bend our head(aah its due to gravity) ...so the area would be bigger when we run...so theres a possiblity of getting wet... but during walking theres less possibility of getting wet...

- 7 years, 1 month ago

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Acc to m it will depend on direction of raining

- 7 years, 1 month ago

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The person who is running gets more wet because the direction of resultant vector of falling rain due to relative velocity will be more tilted towards front (chest & face), wheareas while walking the direction of resultant vector will be more tilted towards top ( head). Therefore more surface area is covered by rain.vector during running so more wet. But here I am talking for same period of time in rain, but not for covering same distance.

- 7 years, 1 month ago

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Take an eg of triangle..in it hypotenuse is greater than perpendicular....so when thean runs the rain falls on him vertically rather than prependicular.so he gets more wet.

- 7 years, 1 month ago

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http://www.youtube.com/watch?v=3MqYE2UuN24 , this video explains it nicely the guys who gets more wet is the one walking

- 7 years, 1 month ago

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One who is walking

- 7 years, 1 month ago

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the one who runs gets more wet because his front is fully exposed for the walker wetting depends on time

- 7 years, 1 month ago

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yeah the person who is walking will get drenched faster... thats why people run to their homes with their filthy umbrellas while it starts to rain... common sense..

- 7 years, 1 month ago

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Both of them will get the same

- 7 years, 1 month ago

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One who is running... Because area exposed to rain will be more.

- 7 years, 1 month ago

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A video from minute physics :) click me~

- 7 years, 1 month ago

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The one who is running

- 7 years, 1 month ago

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Those who voted for "Running", they are ABSOLUTELY wrong. The One, walking, gets more wet. Because whatever you do, You spend much less time if you sprint rather than walk. This is true for even 1 single meter as distance.

- 7 years, 1 month ago

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Proof: http://www.dctech.com/physics/notes/0006.php

- 7 years, 1 month ago

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There is no limitation of time or distense given in the question so do not take ur self condition of time spend in the rain. an if u really want to know the anser u try ur self by spend the time in rain in bothe condition and keep in mind that in bothe there should be same time by adjesting the distense ok my fear . From me it's answer is running

- 7 years, 1 month ago

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Who is walking

- 7 years, 1 month ago

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The one who is running gets more wet!

- 7 years, 1 month ago

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The one who is running maybe?

- 7 years, 1 month ago

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Its like being subjected to extreme heat of the sun and going to a shed. Practically, you'll want to run than to walk. Mathematically speaking, suppose the rain falls in a rate of 1 m^3 per 1 m^{2} per second and the distance between the waiting shed and a bus is 2 m then if you run with a speed 2 m /sec you will only be hit by 1 m^{3} of rain than walking with a speed of 0.5 m/s and getting hit by 4 m^{3} of rain. It is definitely walking.

- 7 years, 1 month ago

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it depends on rain and time.if it is a very heavy rain and takes 10 min if he is running,and 20 min if he is walking,in the both cases wetness will be the same.because there is a limit for wetness.for eg: take two piece of papers of same size,put one paper in a small mug containing water and the other in a swimming pool.then the both paper will wet equally. :)

- 7 years, 1 month ago

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one who is walking

- 7 years, 1 month ago

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Running person who gets wet easily. In an expression,

Wetness = velocity of a man/speed of rainfall... take unitas m/s.

- 7 years, 1 month ago

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depends upon situation

- 7 years, 1 month ago

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One who is walking?

- 7 years, 1 month ago

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running person

- 7 years, 1 month ago

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one who is running gets more rain

- 7 years, 1 month ago

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The one who is running

- 7 years, 1 month ago

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Cosider a example Of shower ... If its vertical thn it wets u cmpltly....(front n back) Bt if its 60 degrees Or say Slightly bent thn it wets u frm one side... .. & it obviously depends upon time..... So The person walking will get wet more.....

- 7 years, 1 month ago

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the one running

- 7 years, 1 month ago

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Equal

- 7 years, 1 month ago

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The one who is running will get wetter.This is because the person who is running will hit the drops that are falling while moving forward.Noneof them can escape the drops that are falling directly on them

- 7 years, 1 month ago

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It should be the one who is walking.

- 7 years, 1 month ago

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One. Who is running

- 7 years, 1 month ago

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One who is running

- 7 years, 1 month ago

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Running man get more wet.

- 7 years, 1 month ago

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running . See this video from you-tube "http://www.youtube.com/watch?v=3MqYE2UuN24"

- 7 years, 1 month ago

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No study in love .......

- 7 years, 1 month ago

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The one who running because he will cover more distance and hence more rain will fall on him and less on walking.

- 7 years, 1 month ago

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The one who is running.....if you are running than rain drops will hits you equals to your running speed.

- 7 years, 1 month ago

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This can be ap proched by imagining in real situation if rain if falling behind u thin u should probably run . by which from relative motion u would observe rain lossing speed

- 7 years, 1 month ago

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Assuming A runs wid velocity u and B is walking wid v.. as the time required for reaching at certain point for B is more he will get more wet as compared to A.

- 7 years, 1 month ago

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While running ,the resultant vector between runner and rain drops will be diagonal so more no. of diagonal components will be experienced by the runner than the waking person who's going experienced less no. of components that is vertical components.

- 7 years, 1 month ago

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The person who is running will get more wet because he will cover more surface area and hence will be more exposed to the rains

- 7 years, 1 month ago

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Those who is running because opposing force against rain will be more in this occasion.so rain drops get scattered & fall on to body

- 7 years, 1 month ago

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depends on relative direction and velocity of rain and man

- 7 years, 1 month ago

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There would be an equal amount of raindrops in a fixed volume while it rains, now let's say one covers X distance while walking and 2x distance while running. Thus in a definite time interval he would have covered double the volume while running thereby getting 2 times more wet than running.

- 7 years, 1 month ago

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Running

- 7 years, 1 month ago

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A running one will get more wet!

- 7 years, 1 month ago

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The one who is running will get more wetted as compared to the one who is walking. This is because the rain drops will get more surface area to wet, more Area is exposed to the raindrops.

- 7 years, 1 month ago

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the one who is walking

- 7 years, 1 month ago

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Guys its all same, it doesnt matter that person is running or walking, if he has to travel 10 mts, thn assume in each 5mts , 50 drops r falling, so, he will definately hit, to 100 drops..

- 7 years, 1 month ago

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one who is running as the rain drops are always slant in motion and if we run we will get more wet

- 7 years, 1 month ago

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One who is running

- 7 years, 1 month ago

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The question is about running or walking and not about the distance which has to b travelled.Therefore one will surely get wet more if runs.

- 7 years ago

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It depends how much time the both were the in rain

- 7 years ago

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The easiest way to think of it is to assume that any given space has the same amount of water, which is functionally true for the question. That means that for the purposes of horizontal movement, the downwards motion of water can be ignored, since it does not change the amount of water in front of you. Thus, how much water you walk into is based on distance (the same as if you were walking through a mist in 0 g). From there, the only variable left is time spent in the rain, since the more time you sit outside, the more water falls on your head. Thus, running gets you less wet.

- 7 years ago

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The man who runs will get more wet

- 6 years, 10 months ago

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the one who is running because the area of hitting rain water on him will be more as compared to that of walking person.on the other hand if the rain is heavy than it doesn't matters weather u r running or walking :).

- 6 years, 9 months ago

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the one,who is running

- 6 years, 9 months ago

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I think if the one is walking is exposed to more rain. If a man is still, then rain only lands on him from the top, but if he is moving, rain is coming from the top and front.

- 7 years, 1 month ago

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The one who is running.

- 7 years, 1 month ago

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One who is walking .

- 7 years, 1 month ago

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Both equal....because,durimg running person is not wet at both the side mainly back side is less wet then front side but front side is speedly wet.And the case of walking person wet both the side front and back but im less amount...

- 7 years, 1 month ago

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The one who is walking get less rain, sure he is walking cause he haa an umbrella 😂

- 7 years, 1 month ago

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running

- 7 years, 1 month ago

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Myth Busters have done this experiment twice to prove this. With the help of a cotton clothing they measured the weight difference and confirmed that the one who walks is comparatively dry. Thanks for all the comments. I appreciate it

- 7 years, 1 month ago

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Wrong dude. They themselves stated that "Our experiment was flawed".

- 7 years, 1 month ago

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The exposed surface area of the person is constant while his velocity differs if we assumed that the weting flow rate is AxV then the running person will get more wet

- 7 years, 1 month ago

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Walking

- 7 years, 1 month ago

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running

- 7 years, 1 month ago

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The one who is walking

- 7 years, 1 month ago

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The one who is walking

- 7 years, 1 month ago

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The one who is moving because the water droplet of eater hits the all parts of the body and the one who is running the water droplet hit only face side in that direction the rain was raining

- 7 years, 1 month ago

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Man walking in the rain gets more wet than running

- 7 years, 1 month ago

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Walking

- 7 years, 1 month ago

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The one who is running will get more wet than the one who is walking

- 7 years, 1 month ago

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The one who is running.

- 7 years, 1 month ago

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Running

- 7 years, 1 month ago

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one who is running

- 7 years, 1 month ago

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It depends on the direction of rain relative to the man!!!

- 7 years, 1 month ago

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The one who is running will get less wet than the one who is walking by actually running opposite to the direction of rain relative to the man.

- 7 years, 1 month ago

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