If the vehicle maintained a constant velocity and there was no air resistance, the diver would enter the pool.
In the real world, air resistance would cause the diver’s velocity to decrease relative to the vehicle and thus the second panel is a probable outcome.
I don’t think you can assume constant velocity. 16 forward movement lines on the top vs 13 on the bottom so it’s moving at 81.25% speed in the bottom compared to the top.
Pretty sure speed lines increase logarithmically with speed, not linearly.
Pretty sure speed lines increase logarithmically with speed, not linearly.
Does this account for the presence of speed holes?
Pretty sure speed lines increase logarithmically with speed, not linearly.
Does this account for the presence of speed holes?
You don’t have to quote the entire reply for them to know what you’re responding to lmao
African or European style?
Wow. I am truly impressed.
You can though, unless the water in the pool has no momentum. It would not be flat if the vehicle was accelerating enough to move that far in a 2-3 second dive.
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This person engineers
It would depend on the speed, and any speed a person could actually stand an jump from is likely slow enough they still land in the pool.
The diver would feel the same wind while in the air as while standing on that elevated diving board. He would recognize the strong 70Mph wind, and jump forward to counteract it.
He wouldn’t be casually standing on the board at 70 mph either, so any wind strong enough to push him off the back would make it really hard to stand and dive in the first place.
He is exerting force on the diving board to stay in position. Gripping with his feet, and leaning.
Sure when you jump you.would.natutslly try to compensate, but I don’t think you’d land where you hope, it would be very hard to gauge the needed force, or even produce it.
Got it, do not attempt while inside the atmosphere
You wouldn’t drive an RV with a pool on the top very fast at all. It’d be a dangerous tipping hazard on any turn, and sudden acceleration or deceleration would cause the water to spill out.
Assuming they’re not going 80, and more likely not even 55, the diver would have more than enough force to jump forward into the water.
I doubt they are fast enough to blow him that far off. My bet would be that he falls flat on the middle of that board.
Idk, have you ever put your hand out the window of the car, going 60k/h? That’s just 50 sq.cm of air resistance… Imagine a whole body’s worth
50cm^2? That’s a baby hand.
OK, if they are going that fast he might just hit his face on the ladder ;-)
Yeah, air resistance and friction from the road are the primary reason why the car’s engine has to keep running.
the woman’s hair is blowing the wrong way
I think it’s supposed to be a fish with a full body mask
Wait, maybe they’re reversing then? This adds new questions.
Maybe the bottom pic comes first chronologically?
It’s tied in a bun I think
That’s not hair
I can’t answer this without at least one spherical cow in the frame of reference.
I’ll allow it on condition it has negligible mass.
Ok but what are its charge and spin values?
This is related to the “airplane on a treadmill” myth (go watch).
Preservation of momentum
I wanna say it’s incorrect, but really I’ll say it’s exaggerated. The man on the diving board is going to continue moving forwards just like the rest of the gear, he’s not going to suddenly stop on relation to the road surface. However, he is going to be affected by wind resistance (which scales
exponentiallyquadratically with speed) so he will need to make a good forward leap in order to not fall behind because of that. If he doesn’t, he would be effective jumping backwards - but not as far as depicted (unless the car is travelling really, really fast).If the pool (and indeed, the man) were encased within an envelope to protect from that wind resistance, he would be entirely unaffected. So there.
It’s not just how fast the car is going. How high the diver jumps (how long he’s in the air) also factors in.
Unless the driver tosses it in neutral, the engine is also still doing work even if keeping the car’s speed constant whereas when the diver jumps, I think he stops being a part of that system he will slow down compared to the van, right? How much this affects the landing of the jump depends upon speed, wind speed, etc.
Thx, fixed. 👌
If the car is accelerating quite jerkly then this should be possible
Or going fast enough that air friction would decelerate the guy this much.
He would need to be gripping extremely hard with his feet and somehow keeping his body rigid in the first panel
I’m imagining him having taken a bit of a run-up and this is the moment when he’s momentarily at the same speed as the car. Obviously, it is still somewhat of a stretch…
Fun fact for anyone reading this, the time derivative of position is velocity, the time derivative of that is acceleration, and the time derivative of that is jerk. Then after that comes snap–>crackle–>pop
The real answer is it depends how the diver is exerting force as he stands there and what force he has to overcome to jump forwards.
If he’s using all his driving force through his legs just to stand there then when he jumps up he will go backwards.
If he was casually standing there easily overcoming the push of the air already then he can jump into the pool just as normal.
It’s the same as standing next to a swimming pool with different wind speeds. Small breeze = jump in ok. Hurricane = blown backwards.
That’s assuming he wasn’t trying to jump off the back of the vehicle…
Also assuming the van doesn’t suddenly, greatly, accelerate
It works if the wind is really strong, but everyone knows physicists can only handle frictionless vacuums
It’s impossible to say how far back the diver would end up relative to the vehicle but from the moment he lost contact with the diving board he’d be subject to deceleration from wind resistance while the vehicle would still be going at whatever speed it already was so seems decently accurate. (Just wait for the Lemmy physics professors to tell me I’m wrong)
Youre not and mythbusters kinda proved this. They shot a ball at 50km/h in one direction while driving in the other, also at 50km/h. The ball stayed in place because they were no longer in contact and their frame of reference is no longer the same and they deal with their own resistances and speed. This means that yes, the diver would lag behind. Maybe not as far as in the comic, depending on car speed, but he would be behind the spot he left on
car would have to be accelerating or… moving fast enough that wind resistance was significant (the air is probably not moving with the car)
If the vehicle is moving at a constant speed, then the guy should be moving at the same speed in the direction of the vehicle during the jump since they’re in the same reference frame, so there’s no reason why he would suddenly lag behind and jump onto the ground.
Edit: Damn physics classes conditioned me into always assuming air resistance is 0!
The vehicle overcomes air resistance with an engine and maintains its speed. The jumper has no engine and will be affected by air resistance
Like the other commenter said, the comic is exaggerated but true
Unless the jumper is farting really hard.
Checkmate.
A head wind would be one reason.
You guys are all confused. The real question is will the diver be injured more by falling on the pavement than diving into such a shallow pool?
If the pool is deep enough to accommodate the diver, then there is no way that car could tow the RV nor any way for those tires to support it, thus the velocity is zero.
The real question is whether his momentum overcomes the wind resistance. Probably not.
The real question is where do you sleep in that camper
Waterbed
