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.

#Mechanics

Note by Vishwesh Ramanathan
7 years ago

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Comments

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

Radha Krishnan B - 7 years ago

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That's the correct answer

Ankur Manna - 6 years, 10 months ago

nice analogy

Varun Narayanan - 6 years, 9 months ago

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

Jimmy Shi - 6 years, 8 months ago

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 :)

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

Calder Hartigan - 7 years ago

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Me too!

Jason Yao - 6 years, 12 months ago

SAME

Varun Narayanan - 6 years, 9 months ago

"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

Jayant Kumar - 7 years 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"

Jayant Kumar - 7 years ago

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.

Evan Acuna - 6 years, 11 months ago

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.

Abhi gupta - 7 years ago

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

Yu Xuan Teo - 6 years, 11 months ago

Umbrella mam

Vrutant Patel - 6 years, 11 months ago

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

Avineil Jain - 7 years ago

The one who is walking .

Nashita Rahman - 7 years ago

The man who is running will get more wet.

Romy Das - 7 years ago

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.

Chris Hambacher - 7 years ago

one who is running gets more wet.

ANESHA Haneefa - 7 years ago

the walker with more vectors added in same direction

Shubham Bhardwaj - 7 years ago

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...

Aniruddha Halder - 7 years ago

Acc to m it will depend on direction of raining

Piyush Unique - 7 years ago

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.

Arpan Mishra - 7 years ago

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.

Himanshu Singla - 7 years ago

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

jeronim matijevic - 7 years ago

One who is walking

imad zaim - 7 years ago

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

Hema Kumar - 6 years, 12 months ago

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..

Shraman Das - 6 years, 12 months ago

Both of them will get the same

AJ Telles - 6 years, 12 months ago

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

shree harry - 6 years, 12 months ago

A video from minute physics :) click me~

Amanda Hm - 6 years, 12 months ago

The one who is running

ASHISH GUPTA - 6 years, 12 months ago

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.

Ask Amn - 6 years, 12 months ago

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

Ask Amn - 6 years, 12 months ago

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

rakesh singh - 6 years, 11 months ago

Who is walking

Mayank Bansal - 6 years, 12 months ago

The one who is running gets more wet!

Utkarsh Dagor - 6 years, 12 months ago

The one who is running maybe?

Afnan Al-Qassam - 6 years, 12 months ago

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.

Leonardo Arcenal Jr - 6 years, 12 months ago

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. :)

Sreehari Vp - 6 years, 12 months ago

one who is walking

Lovely Mish - 6 years, 12 months ago

Running person who gets wet easily. In an expression,

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

Dinesh kumar - 6 years, 12 months ago

depends upon situation

Bipin Sharma - 6 years, 12 months ago

One who is walking?

hannaj may tan - 6 years, 12 months ago

running person

Sai Lakshmi Cheedella - 6 years, 12 months ago

one who is running gets more rain

abhishek sharma - 6 years, 12 months ago

The one who is running

Abhishek Singh - 6 years, 12 months ago

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.....

Jayesh Mayenkar - 6 years, 12 months ago

the one running

anshul aggarwal - 6 years, 12 months ago

Equal

mohamed hosny - 6 years, 12 months ago

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

Platinum Grieger - 6 years, 12 months ago

It should be the one who is walking.

Anuj Shikarkhane - 6 years, 12 months ago

One. Who is running

sandy whiz - 6 years, 11 months ago

One who is running

Prahul Bhudia - 6 years, 11 months ago

Running man get more wet.

Inzamam Ashraf - 6 years, 11 months ago

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

Abhik Adak - 6 years, 11 months ago

No study in love .......

Beenish Yamin - 6 years, 11 months ago

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

Jabir Ansari - 6 years, 11 months ago

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

Ashish Bansal - 6 years, 11 months ago

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

Ajinkya Takawale - 6 years, 11 months ago

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.

V'shal Bhosale - 6 years, 11 months ago

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.

Subho Karmakar - 6 years, 11 months ago

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

apoorv pachori - 6 years, 11 months ago

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

Sandeep Csagaran - 6 years, 11 months ago

depends on relative direction and velocity of rain and man

Tarun Rajoria - 6 years, 11 months ago

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.

Er Suraj Kar - 6 years, 11 months ago

Running

rakesh singh - 6 years, 11 months ago

A running one will get more wet!

sachin thakur - 6 years, 11 months ago

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.

Harshit Dahiya - 6 years, 11 months ago

the one who is walking

Majestic Riajil - 6 years, 11 months ago

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..

Ridham Trivedi - 6 years, 11 months ago

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

Mishit Shah Shah - 6 years, 11 months ago

One who is running

prasanna kumar - 6 years, 11 months ago

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.

Chirag TTomar - 6 years, 11 months ago

It depends how much time the both were the in rain

Ravindra Shigli - 6 years, 11 months ago

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.

Colin Guo - 6 years, 10 months ago

The man who runs will get more wet

Anuj Agarwal - 6 years, 9 months ago

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 :).

Saurabh Yadav - 6 years, 8 months ago

the one,who is running

sujan dalbehera - 6 years, 8 months ago

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.

Jimmy Shi - 7 years ago

The one who is running.

Teddy Palas - 7 years ago

One who is walking .

Beenish Yamin - 7 years ago

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...

Tarun Sanepara - 7 years ago

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

Abdo Ahmed - 7 years ago

running

akshat asthana - 7 years ago

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

Vishwesh Ramanathan - 6 years, 12 months ago

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

Ask Amn - 6 years, 12 months ago

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

Mohamed El-nagdy - 6 years, 12 months ago

Walking

Chippy Sadhasivam - 6 years, 12 months ago

running

Billy Gelaga - 6 years, 12 months ago

The one who is walking

Sudhanshu Rocky - 6 years, 11 months ago

The one who is walking

Himanshi Chawla - 6 years, 11 months ago

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

Piyush Pallav - 6 years, 11 months ago

Man walking in the rain gets more wet than running

uday kumar - 6 years, 11 months ago

Walking

Martin Davis - 6 years, 11 months ago

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

Akash Bhansali - 7 years ago

The one who is running.

Saranya Gopinath - 7 years ago

Running

Nitin Sahatya - 7 years ago

one who is running

Dastgir Shaown - 7 years ago

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

Yash Kodesia - 7 years 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.

Ramji Varadarajan - 7 years ago
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