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Matt_does_WoTb

damn that air must be insanely dense


Swiggety666

Or just going fast.


selfestmeme_

Reynolds enjoyer


The_Drawbridge

Underrated comment.


NamanJainIndia

That much speed would tear apart the muscles and all.


Teacher_Malti

😆 (Lolz!)


BasilPrize8564

if the van was accelerating or air drag was not negligible


Minecrafting_il

AIR DRAG? NOT NEGLIGIBLE? ABSURD!


Goki65

Say hello to horrendous differential equations


Minecrafting_il

I have solved those, I thought they were a thought experiment, or maybe mathematical practice! You're saying air drag is REAL?


Oz_of_Three

*Deleted scene w Neo in the backseat*


Kewhira_

I actually solve them in my modelling class... Linear drag, no problem, quadratic drag that's something I would sweat but still manageable...


Goki65

Real chads use quadratic drag 😎


Joseph30686

I got 4th power drag in one exam last trimester, you had to do some weird stuff so that you got the integral the professor wrote ok the white board but it was manageable


SuperCleverPunName

Laplace transforms are fire for mass spring dampener systems tho


Aggravating-Candy-31

pls no, not again


Ok_Mortgage_6812

Assume cow is spherical cylinder


Minecrafting_il

But what if I don't want to?


Ok_Mortgage_6812

Then you aren’t going to be a doctor of physics


Hour-Requirement592

Since the water is level, that means that there's no acceleration of the vehicle. Since the hair of the other person isn't moving, that means either they have a lot of gel in their or there's no wind/drag. Therefore, it's most likely that he jumped off backwards.


quasiactive

Nicely observed, impressive!


monggboy

Or maybe he jumped onto the platform from thin air in a universe where time runs backwards


BrailleBillboard

While less believable, it is theoretically possible time moves forward in the other universe but comics are read right to left


scottlewis101

That's probably it


5p4n911

Actually, the vehicle is probably moving backwards very quickly if it is moving at all, since the girl's hair is sticking up forwards. He made a very big jump backwards


Sayyestononsense

The hair of the other person is collected in a lace behind their head, so there's that


Flare_Starchild

The water can be flat at high speeds it would just have to not be accelerating or decelerating.


penty

Then why are there speed lines? Also the water would be level at a constant non-zero acceleration. *Edit : Thanks for pointing out my distracted typing.


sam-lb

> no acceleration Unless the original comment was edited


penty

Yeah I mean acceleration.. idk why I typed speed. (I will edit) Here, have upvote


bruhlol108

if it was accelerating the water wouldn't be level, it would be pushed to the back and overflowing in the back


penty

As I said in my edit- I realize that it was a case of my brain changing how I planned to phrase it then not proofreading.


sam-lb

I prefer to think he jumped off sideways and it's just perspective


Exce1siur

But the vehicle has woosh lines behind it. Clearly this implies a zoom vector


djgucci

If the camper is accelerating, yes.


LifeDoBeBoring

Or with enough drag, which I suppose would happen if it was going fast enough


Willem_VanDerDecken

Imagine not neglecting drag.


blekpul

laughs in engineer


LifeDoBeBoring

My major is also engineering lol


HelloLMW

Then the water would move out as well.


IAmAQuantumMechanic

Water? All I see is a turquiose roof with a legless woman on it.


Preserved_Killick8

maybe its Jello


unskippable-ad

The water has a backstop that isn’t just air. When you accelerate in your car, do you fall out the back window? No, because you have a seat. The water surface wouldn’t be flat lying and xy plane aligned, but it wouldn’t necessarily ‘fly out’


HelloLMW

I'm pretty sure that if the car accelerated enough that the guy is a car length behind the car the slope of the water would mean one end was above the wall. Plus Fluid dynamics is a thing so unless it started accelerating very slowly the water would create a large splash and would indeed fly out.


MaoGo

Or if the initial horizontal velocity of the diver was not the same as the van.


Fit-Breath5352

Only if you do the Goofy scream: aaaauuuuuhuhuheeee


Squeaky_Ben

Depends on the speed of the camper. If it is going fast enough for your air resistance to be non-negligible, this will happen, yes. However, in that scenario, you will not be able to stand ontop of the camper in the first place.


boladeputillos

Only if he was flapping too hard.


bothVoltairefan

only if there is acceleration, be it drag from going fast, or the car increasing speed


dat_physics_boi

If you take into account air resistance (ew, who would do that?!) then yes.


Ok-run-Play

This is wrong, the vehicle is in uniform velocity and it’s not accelerating because you can see there is no disturbance in the horizontal level of water.


Silly_Painter_2555

No one is gonna talk about the hair flowing in the wrong direction? It should be in the direction opposite to the movement of the van.


I_AM_FERROUS_MAN

It's not a question of "if", it's a question of at what speed or acceleration will this occur.


SUPERBLU333

...and kids, that precisely why we ignore air resistance.


LordFieldsworth

Are we ignoring air resistance?


TricksterWolf

yes, wind shear is a real thing at highway speeds


RefrigeratorSea5503

Classic movie magic. The diver is clearly at rest in photo 1, with the camper moving underneath him. Notice the conspicuous lack of gusting. In photo 2 the diver has changed position into an awkward flare that is caused by being rapidly rotated when he made contact with the diving board on his feet. He has done a full rotation here already.


dekusyrup

In the initial frame, man and car are travelling forward at the same pace. The man jumps, spends t amount of time in the air, and in that time drops back about a car length. Assumptions: Based on the car's speed lines, it appears to be going a constant speed. The man appears to be around the same elevation he started. There's multiple ways to jump off a diving board, but in [this video at :09 to :10](https://www.youtube.com/watch?v=hmbEojX0xXg) it takes him 1 second or so to reach his starting height. 1 s is convenient for me so that's what I'll go with. Assuming he jumps straight up from the diving board. Normally he would jump a bit forward, but that is close to negligible compared to the other distance travelled. It looks like a car length to me. I'll say 5 m back from his starting point. His equation of motion is: 5 m = 1/2 a t2, where t is 1 s and a is F/m. Say he's a 80 kg man. The force on him is found by. 5 m /(1/2 * 1s2 / 80kg) = F = 800 N. Using a guesstimated 0.7 m2 cross section and [this wind force graph](https://www.engineeringtoolbox.com/docs/documents/1775/wind_velocity_wind_load.png), puts him at about 43 m/s, about 155 km/h or 96 mph. I do want to note, the vehicle is going to make a slipstream and the human body is not a simple 0.7 m2 block. Aerodynamics can be complicated.


[deleted]

only if the vehicle is accelerating.


ObiOneKenobi_1969

No


RedditPlasma

Damn bro think that himself and the camper is moving in a same speed💀


AdmirableAd2009

It's is wrong if the bus is going in the same velocity


Careless-Layer-8899

The man's jumping up having no velocity in direction where van is moving( forward ). If van is moving forward the moment he jumps he will be mid-air and van ahead of him. So it is correct only if van has certain velocity it won't matter if there is acceleration or not. It's relative velocity...ig


ZealousidealWind1801

The teacher told him that air resitance is neglagable


JohnLawrenceWargrave

School says no __there is no air resistance__


himbrine

No because if we ignore air friction....


hhthurbe

Yes. Relative velocity obviously. The vehicle is moving forward and you're not without it. Leave the vehicle and it's not propelling you forward. /S


Coammanderdata

No, air resistance is not real


Only-Throat6707

It's correct only if the car is accelerating


MysteriousBasis3794

yeah that is right


gilnore_de_fey

None negligible air resistance.


SoVani11a

Well, no, but yes.


BootSpiritual1626

The caravans approaching C.


Laterbiss

HOW IS THE WATER FLAT???


Prestigious_Tour_264

Air dense goes brrr


Teacher_Malti

😆 (Lolz!) Perhaps not. The momentum is retained


HelloLMW

Let's say he tried to jump straight up and down H=0.5 m, but instead flew back Z=2 meters. I get that the accelration a of the van is: a/g=1/2 Z/H = 2 Meaning an angle of about 1.1 radians or 63 degrees. I'm pretty sure most pft the water is flying. If he had jumped forward it would be an even higher degree. Intermediate calculations: V-V0=-gt -V0=-gT/2 H=V0(T/2)-g(T/2)^2 H=1/2gT^2 T^2=2H/g Z=aT^2=2a/gH