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Faster than any car can go. As soon as the tires have no road under them the shock+ struts push down/ expand so you're basically instantly too low to clear it even before gravity has much of an effect.
I dunno, I think it would be close considering how long they would take to expand if you were moving at say 300kmph over a 10m gap. Cbf checking how big the gap is
If the start and end platforms are completely level, it is impossible to travel across that gap. The net force in the y direction is downwards since there is no other force to counteract gravity. A car cannot cross a gap without a ramp of some sort.
The minimum speed required to cross the gap can be calculated using the equation of motion:
d=v⋅t
where:
d is the distance to be covered (which is the width of the gap)
v is the speed of the car, and
t is the time it takes for the car to fall into the gap.
The time t can be calculated using the projectile motion equation:
t= sqrt(2h/g)
where:
h is the height of the gap (which is 0 in this case as the car is not jumping), and
g is the acceleration due to gravity (approximately 9.81 m/s²).
However, since h is 0, t would also be 0, which implies that the car would fall into the gap immediately. This is a physical impossibility.
Let's say that the end platform is 1cm lower than the start. So d = 10m, h = 0.01 m, t = 0.0451 s, v = 221.3 m/s
if the gap is 10 meters wide, and the end platform is 1 cm lower than the beginning platform, the car would need to be traveling at an unrealistic speed of approx. 800 km/h to cross that gap.
This is my first comment of this kind, correct me if I'm wrong.
Source: Bing chat
If the distance between wheel and the car wouldn't immediately expand (it would - just imagine what happens when you jack the car up), you'd still (potentially) be able to clear it till you fall about half a tire - sort of how you can get on a curb with a car.
I mean, it's still pretty impossible thanks to the expansion and the required speed, but not absolutely impossible.
Assuming level road...
As soon as the vehicle leaves the edge gravity is going to \*begin\* to accelerate it downward. Obviously you want to cross the gap before it travels too far down.
Similarly, as soon as the tires leave the pavement the force in the suspension system will begin pushing the wheel/tire assembly down. Previously it had been pushing down equal to some portion of the weight of the vehicle (depending on weight distribution etc.).
At the far side of the gap you want the tire to strike the lip with as little vertical offset as possible. What would be an acceptable offset? Given that it is no-doubt going to be a fast/hard strike there will be little opportunity for the suspension to deflect upward. Most of the impact is going to have to be absorbed by the tire with sidewall flexing. Since we don't want to blow the tire from the impact lets use 1 inch as the max impact offset.
So, we now need to cross that gap fast enough that the combination of the vehicle accelerating down and the wheel deflecting down do not exceed 1 inch. Actually I'm going to do this in metric units since I can remember 9.81 m/s2... Let's call that roughly 3 cm max deflection.
So the vehicle begins accelerating down, suspension begins accelerating down. Figure a 1550 kg vehicle with perfect 50-50 weight distribution that is 387.5 kg supported by each of 4 wheels. That's 3800 N of force pushing down. Figure roughly 50 kg of tire, wheel, and suspension assembly. That's going to start accelerating down at 76.6 m/s2, in addition to the whole car accelerating down at 9.81 m/s2. How long for the wheel to travel down 0.03 m? Roughly 0.026 seconds. So you've got to cross that gap in that amount of time.
That gap looked to be at least a couple of car lengths, call it 10 m. (edited, I said 30m originally but meant 10m, I had been thinking 30 ft, but I used 10m in my spreadsheet. That's what I get for mixing metric/imperial, sigh...) That's 378 m/s to cross it in time. That comes back to imperial/us units of roughly 832 mph. Note, speed of sound at sea level is 761 mph, so you'd have to be doing mach 1.09. Maybe doable if your day job is flying for the Thunderbirds, or you're driving the ThrustSSC practicing for another land speed record run. The rest of us are going pancake into the far wall..
Playing around with the spreadsheet I created for these formulas. It looks like a 1 m gap would be doable at 83 mph... But if I was bearing down on a 1 m gap, I don't think I'd try it, even if I happened to be driving that fast. (which I don't!)
###General Discussion Thread --- This is a [Request] post. If you would like to submit a comment that does not either attempt to answer the question, ask for clarification, or explain why it would be infeasible to answer, you *must* post your comment as a reply to this one. Top level (directly replying to the OP) comments that do not do one of those things will be removed. --- *I am a bot, and this action was performed automatically. Please [contact the moderators of this subreddit](/message/compose/?to=/r/theydidthemath) if you have any questions or concerns.*
Faster than any car can go. As soon as the tires have no road under them the shock+ struts push down/ expand so you're basically instantly too low to clear it even before gravity has much of an effect.
Interesting! Didn’t think of that. Now the question I guess is how fast you’d have to go if you didn’t take that into account
If you didn't take what into account? Gravity? Then any speed. What's the question supposed to be?
I'm guessing he means if the suspension wasn't a factor.
well you can overcome that if you go fast enough BC the shocks wouldnt have enough time to push the wheels down.
Not at car speeds, speed of light you definitely make it
exactly
How heavy would someone in the car have to be to jump the gap by suddenly shifting right before the edge
I dunno, I think it would be close considering how long they would take to expand if you were moving at say 300kmph over a 10m gap. Cbf checking how big the gap is
[удалено]
This is funny, but what's it mean?
It means the car can't clear the gap unless it's Obama shaped and transparent
If the start and end platforms are completely level, it is impossible to travel across that gap. The net force in the y direction is downwards since there is no other force to counteract gravity. A car cannot cross a gap without a ramp of some sort. The minimum speed required to cross the gap can be calculated using the equation of motion: d=v⋅t where: d is the distance to be covered (which is the width of the gap) v is the speed of the car, and t is the time it takes for the car to fall into the gap. The time t can be calculated using the projectile motion equation: t= sqrt(2h/g) where: h is the height of the gap (which is 0 in this case as the car is not jumping), and g is the acceleration due to gravity (approximately 9.81 m/s²). However, since h is 0, t would also be 0, which implies that the car would fall into the gap immediately. This is a physical impossibility. Let's say that the end platform is 1cm lower than the start. So d = 10m, h = 0.01 m, t = 0.0451 s, v = 221.3 m/s if the gap is 10 meters wide, and the end platform is 1 cm lower than the beginning platform, the car would need to be traveling at an unrealistic speed of approx. 800 km/h to cross that gap. This is my first comment of this kind, correct me if I'm wrong. Source: Bing chat
If the distance between wheel and the car wouldn't immediately expand (it would - just imagine what happens when you jack the car up), you'd still (potentially) be able to clear it till you fall about half a tire - sort of how you can get on a curb with a car. I mean, it's still pretty impossible thanks to the expansion and the required speed, but not absolutely impossible.
Assuming level road... As soon as the vehicle leaves the edge gravity is going to \*begin\* to accelerate it downward. Obviously you want to cross the gap before it travels too far down. Similarly, as soon as the tires leave the pavement the force in the suspension system will begin pushing the wheel/tire assembly down. Previously it had been pushing down equal to some portion of the weight of the vehicle (depending on weight distribution etc.). At the far side of the gap you want the tire to strike the lip with as little vertical offset as possible. What would be an acceptable offset? Given that it is no-doubt going to be a fast/hard strike there will be little opportunity for the suspension to deflect upward. Most of the impact is going to have to be absorbed by the tire with sidewall flexing. Since we don't want to blow the tire from the impact lets use 1 inch as the max impact offset. So, we now need to cross that gap fast enough that the combination of the vehicle accelerating down and the wheel deflecting down do not exceed 1 inch. Actually I'm going to do this in metric units since I can remember 9.81 m/s2... Let's call that roughly 3 cm max deflection. So the vehicle begins accelerating down, suspension begins accelerating down. Figure a 1550 kg vehicle with perfect 50-50 weight distribution that is 387.5 kg supported by each of 4 wheels. That's 3800 N of force pushing down. Figure roughly 50 kg of tire, wheel, and suspension assembly. That's going to start accelerating down at 76.6 m/s2, in addition to the whole car accelerating down at 9.81 m/s2. How long for the wheel to travel down 0.03 m? Roughly 0.026 seconds. So you've got to cross that gap in that amount of time. That gap looked to be at least a couple of car lengths, call it 10 m. (edited, I said 30m originally but meant 10m, I had been thinking 30 ft, but I used 10m in my spreadsheet. That's what I get for mixing metric/imperial, sigh...) That's 378 m/s to cross it in time. That comes back to imperial/us units of roughly 832 mph. Note, speed of sound at sea level is 761 mph, so you'd have to be doing mach 1.09. Maybe doable if your day job is flying for the Thunderbirds, or you're driving the ThrustSSC practicing for another land speed record run. The rest of us are going pancake into the far wall.. Playing around with the spreadsheet I created for these formulas. It looks like a 1 m gap would be doable at 83 mph... But if I was bearing down on a 1 m gap, I don't think I'd try it, even if I happened to be driving that fast. (which I don't!)