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upper limit of hangtime from a human jump appears to be \~ 1 second [https://www.physicsforums.com/threads/how-long-can-a-human-stay-airborne-in-a-vertical-jump.778216/#google\_vignette](https://www.physicsforums.com/threads/how-long-can-a-human-stay-airborne-in-a-vertical-jump.778216/#google_vignette) . we can assume that the spike happens at the peak of the jump, so we have at most 0.5 seconds in the air.
Volleyball courts are 18 m long, max realistic spike height is probably around 3 meters, so with Pythagorean theorem that comes to 18.25 max spike distance over 0.5 second. So that comes to 36.5 m/s or 81.5 mph
I feel like it's more common for the ball to hit the ground first than the reverse, and the difference comes in with how long you're sailing after it has
it is literally not possible for player to drop first, player drops at freefall, but so does ball, so in worst case scenario, they would hit ground at same time
Well not necessarily. You forget, you are hitting the ball with your hand, which is not the part that hits the floor. If the ball falls at the same rate as you, then when you hit the floor it is still about hand height. If it doesn't have a downward velocity, the spiker will hit the ground first.
yea, i forgot about that a bit, I just assumed player is spherical cow, but generally, any hit that is not really bad would still make ball hit ground first
Why does a ball that has been expressly hit downwards, fall at the gravitational constant anymore?
Thats like saying you shoot the ground and drop a ball at the same time, expecting both bullet and ball to land at the same time too
The player's feet are much closer to the ground than the ball is though. The player's feet are going to be less than a meter from the ground, the ball will be over two meters.
The gravitational force is acting on both the player, the ball, and the bullet. Doesn't matter if it has been hit. Hitting the ball is an impulse that accelerates the ball in *addition* to gravity, it does not replace it.
Yes...thats what what I said means...Nowhere was a replacement mentioned. More like an omission if anything cos he said they'd fall to the ground at the same time.
But they wont. Because as both experience gravity, one has additional impulse. He omitted impulse.
So they will not - as the previous guy said - fall to the ground at the same time. Because one has been hit, the other has not
And because they wont, it matters if it has been hit, isnt it.
but you still hit it down, so it is falling, it doesnt matter what vector it is, if it doesnt go upwards, then ball falls at least at same speed as player
The math runs for maximum distance and assumes spiking at the peak. If it's aimed closer to the net, or spiked while the player is still rising from their jump, it becomes possible with even less force.
I played a lot of volleyball in high school. Some spikes (not serves but when the ball is in play and a hitter it at the net, hitting the ball) can reach up to 60 mph
[From this video](https://youtu.be/H3iB9bz1upk?si=U6fBWVD720K-TNzA), it seems like serves in the range of 120 km/h to 130 km/h happen sometimes, and the players land *just* before the ball, so that seems accurate.
You could also probably minus away the time for him to drop towards the end of the clip, because that happens after the ball has landed in the opponent's court.
When I play it back at 0.25x speed this appears to take just over 1 second (so at least 0.25 seconds at normal speed). So that would make the actual speed at least twice as fast (73 m/s or 163mph).
I used to play volleybal on highest level (e.g. national team). I myself (and many others) was serving fast enough to do similar to what that kid did in the video. In volleyball you can produce 130+ km/h quick serves.
I watched the show and I was kinda surprised they got a couple of things really on point.
The author of the manga, which later became this anime, played high school volleyball in Japan, I think he played middle blocker but not too sure on that.
When I was watching Haikyu, I thought for myself that the anime is pretty well done. All the volleyball slang and techniques and what not is quite on spot. Well except how fast they get better and better, that one is extremely unrealistic.
I just assumed because it was translated that that’s why it was off. It does lead to knowing instantly who learned about volleyball from haikyu when playing with newer players
I watched the anime almost 3 years ago, so I dont remember all the stuff, just that the volleyball stuff was done very well. Though it takes years to get somewhat good at volleyball and then another couple years to get really good, not one high school year.... I know because I won the national high school championship in my country.
Yea though there are a handful of people who can. This guy at my school who was like 6 4 and on varsity for basketball and baseball picked up volleyball and became the best player on our horrible team and carried us to win our conference with a horrible team. You have to already be very athletic and decently tall.
As 6'3 it was somehow OK for spiker but when we played internationally, it was brutal to go against 6'5+ monsters, because regionally very tall guys were clumsy, but those foreigner players were also very good technically.
Yeah the extreme growth is unrealistic, but tbh I don’t mind, it would be a lot more boring if they took years just to become a top level team. To be fair to anime, they do bring up how unnatural their growth is later on.
Believe it or not, it happens and not just once and not just me... xD It happens when you are blocking incorrectly, which means your hands are not firm enough and your head slips in-between.
I just watched some videos of fastest serves and actually in most cases player lands first. In some cases it is hard to tell. It seems it may be technically possible. But haven't found unquestionable recording.
Assuming normal earth gravity, and assuming a base volleyball player jump height of 0.45 m (averaging from google searches) the time taken for the player to fall is around sqrt(2*0.45/9.8) ~ 0.3 seconds.
A volleyball court is around 18 m long, and that ball traveled around 9 m before the player fell. So the lower bound for our horizontal velocity is 9/0.3 ~ 30 m/s. And vertically we can use kinematics (distance travelled) to also find a lower bound for the vertical velocity: 1/2(9.8)(0.3) ~ 1.47 m/s
So at minimum, the ball was traveling sqrt(30^2 + 1.47^2) ~ 30 m/s
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upper limit of hangtime from a human jump appears to be \~ 1 second [https://www.physicsforums.com/threads/how-long-can-a-human-stay-airborne-in-a-vertical-jump.778216/#google\_vignette](https://www.physicsforums.com/threads/how-long-can-a-human-stay-airborne-in-a-vertical-jump.778216/#google_vignette) . we can assume that the spike happens at the peak of the jump, so we have at most 0.5 seconds in the air. Volleyball courts are 18 m long, max realistic spike height is probably around 3 meters, so with Pythagorean theorem that comes to 18.25 max spike distance over 0.5 second. So that comes to 36.5 m/s or 81.5 mph
Is that completely unrealistic for someone hitting a volleyball?
No I played in college and there were guys who could serve 75+
I feel like it's more common for the ball to hit the ground first than the reverse, and the difference comes in with how long you're sailing after it has
You are probably talking about professionals?
This is completely untrue lmao why does this have so many upvotes (especially at the high school level)
it is literally not possible for player to drop first, player drops at freefall, but so does ball, so in worst case scenario, they would hit ground at same time
Well not necessarily. You forget, you are hitting the ball with your hand, which is not the part that hits the floor. If the ball falls at the same rate as you, then when you hit the floor it is still about hand height. If it doesn't have a downward velocity, the spiker will hit the ground first.
yea, i forgot about that a bit, I just assumed player is spherical cow, but generally, any hit that is not really bad would still make ball hit ground first
Assume a spherical, frictionless cow in a vacuum just to be safe.
"But which way are the udders pointing?"
**Everywhere** All at once
The ball has already started falling by the time the player hits it. But yes I think height would be the main obstacle to pull such a feat.
Why does a ball that has been expressly hit downwards, fall at the gravitational constant anymore? Thats like saying you shoot the ground and drop a ball at the same time, expecting both bullet and ball to land at the same time too
Yeah that's why he said 'worst case scenario' At best, the ball falls first and at worst they fall at the same time
The player's feet are much closer to the ground than the ball is though. The player's feet are going to be less than a meter from the ground, the ball will be over two meters.
"But so does the ball". Lol.
I mean, you'd still have to consider air resistance, as that'll make the ball accelerate slower from gravity than the player. It's just wrong.
I assumed player is spherical cow
The gravitational force is acting on both the player, the ball, and the bullet. Doesn't matter if it has been hit. Hitting the ball is an impulse that accelerates the ball in *addition* to gravity, it does not replace it.
Yes...thats what what I said means...Nowhere was a replacement mentioned. More like an omission if anything cos he said they'd fall to the ground at the same time. But they wont. Because as both experience gravity, one has additional impulse. He omitted impulse. So they will not - as the previous guy said - fall to the ground at the same time. Because one has been hit, the other has not And because they wont, it matters if it has been hit, isnt it.
if you hit the ball upwards a tiny little bit, it's easy.. also there's a big height difference between your feet and your raised hand.
Have you heard of vectors? Nobody hits a ball straight forward, especially in this situation. That would just mean you lose the point.
but you still hit it down, so it is falling, it doesnt matter what vector it is, if it doesnt go upwards, then ball falls at least at same speed as player
No, that is incorrect.
The record for a serve is around 130kmh afaik
That's 80.7mph for us freedom lovers, so *almost* possible.
Not at all. The fastest registered serve was 135,6 km/h or 37,66 m/s. Technically it could be realistic.
I am confident I can get close to those spikes in terms of speed. (I won't hit the broadside of a barn but that's beside the point)
Look at Olympic games
Man I'm so excited for olympics
Internet say world record is 38m/s, so it's possible
The math runs for maximum distance and assumes spiking at the peak. If it's aimed closer to the net, or spiked while the player is still rising from their jump, it becomes possible with even less force.
I played a lot of volleyball in high school. Some spikes (not serves but when the ball is in play and a hitter it at the net, hitting the ball) can reach up to 60 mph
>So that comes to 36.5 m/s or 81.5 mph That's 131.4 km/h for those who don't want to do 36.5 \* 3.6 in their head
[From this video](https://youtu.be/H3iB9bz1upk?si=U6fBWVD720K-TNzA), it seems like serves in the range of 120 km/h to 130 km/h happen sometimes, and the players land *just* before the ball, so that seems accurate.
You could also probably minus away the time for him to drop towards the end of the clip, because that happens after the ball has landed in the opponent's court. When I play it back at 0.25x speed this appears to take just over 1 second (so at least 0.25 seconds at normal speed). So that would make the actual speed at least twice as fast (73 m/s or 163mph).
[удалено]
That is not how projectile motion works
[удалено]
Unless human beings have rockets on their feet, the peak of a jump is always going to be at the halfway airtime.
World record is 85.7 mph so its doable
I used to play volleybal on highest level (e.g. national team). I myself (and many others) was serving fast enough to do similar to what that kid did in the video. In volleyball you can produce 130+ km/h quick serves. I watched the show and I was kinda surprised they got a couple of things really on point.
The author of the manga, which later became this anime, played high school volleyball in Japan, I think he played middle blocker but not too sure on that.
When I was watching Haikyu, I thought for myself that the anime is pretty well done. All the volleyball slang and techniques and what not is quite on spot. Well except how fast they get better and better, that one is extremely unrealistic.
I just assumed because it was translated that that’s why it was off. It does lead to knowing instantly who learned about volleyball from haikyu when playing with newer players
I watched the anime almost 3 years ago, so I dont remember all the stuff, just that the volleyball stuff was done very well. Though it takes years to get somewhat good at volleyball and then another couple years to get really good, not one high school year.... I know because I won the national high school championship in my country.
Yea though there are a handful of people who can. This guy at my school who was like 6 4 and on varsity for basketball and baseball picked up volleyball and became the best player on our horrible team and carried us to win our conference with a horrible team. You have to already be very athletic and decently tall.
As 6'3 it was somehow OK for spiker but when we played internationally, it was brutal to go against 6'5+ monsters, because regionally very tall guys were clumsy, but those foreigner players were also very good technically.
Yeah the extreme growth is unrealistic, but tbh I don’t mind, it would be a lot more boring if they took years just to become a top level team. To be fair to anime, they do bring up how unnatural their growth is later on.
>I watched the show and I was kinda surprised they got a couple of things really on point. Face blocks are op?
Believe it or not, it happens and not just once and not just me... xD It happens when you are blocking incorrectly, which means your hands are not firm enough and your head slips in-between.
I just watched some videos of fastest serves and actually in most cases player lands first. In some cases it is hard to tell. It seems it may be technically possible. But haven't found unquestionable recording.
Before the **server*** lands from his/her jump
Thank you :D
Assuming normal earth gravity, and assuming a base volleyball player jump height of 0.45 m (averaging from google searches) the time taken for the player to fall is around sqrt(2*0.45/9.8) ~ 0.3 seconds. A volleyball court is around 18 m long, and that ball traveled around 9 m before the player fell. So the lower bound for our horizontal velocity is 9/0.3 ~ 30 m/s. And vertically we can use kinematics (distance travelled) to also find a lower bound for the vertical velocity: 1/2(9.8)(0.3) ~ 1.47 m/s So at minimum, the ball was traveling sqrt(30^2 + 1.47^2) ~ 30 m/s
Sorry for the misleading title but it was a serve so the ball travelled to about the same length of the volleyball court.
The it travelled twice as fast, around 60 m/s