In this scene, the soccer ball was kicked by a player with a tremendous force. The Lightning hand Goalie (Forth Brother) stops the ball, but fly back because of the reaction force.This scene is an example of bad physics because it is unrealistic that a human can actually take off/fly after been hit by a soccer ball. Let us assume the following:-A soccer ball is usually weight 15 pounds = 0.4kg in Fifa games -We can’t simply calculate the velocity of the ball that the guy kicked in the movie. So i used the world record for the hardest recorded shot in Soccer. Which is 114mph = 50 m/s, performed by Daivd Hirst in 1996Find how long a soccer field is and the time traveled -the official length of the soccer field is 90m long. the guy who kicked the ball stands right between the half line and the penalty area, so about a quarter of 90 m, which is 22.5 m22.5/50=0.45sm=0.4kgt=0.45sv=50m/sFind the amount of force acting on the person by the soccer balla=delta v/tFnet=ma =(0.4)(50/0.45) =44.4 N44.4N is about the same as holding an object that is 4.4Kg.
So in real life, if you kicked a ball at someone with the same force as the world record of hardest soccer ball kick, this might be able hit someone and make them step back or sit down; but certainly itâ€™s not enough force to knock a person 10 feet above ground.-In addition, if you look at the beginning of the scene; when the guy kicks the ball and the ball was flying towards the net, there was no sign that the ball was affected by the force of gravity.) In this scene, the Shaolin team has just found their inner kung-fu by beating the group of thugs and is now playing their first important match. Sing uses his powerful leg to score and immediately gets a goal.How about the physics?Well, as you can see in the clip, when he kicks the ball it looks like he exerts quite a bit of force. However, when he scores the goal the net does not even move an inch. The net should have moved to imitate the reaction force of the ball acting on the net. Instead the force of the ball travelling towards the net did not have any effect.Let’s assume that Sing has used the average kick of a professional soccer player, which means the ball is travelling at approximately 30 m/s (1) and that the soccer ball is the average mass of a size 5 outdoor soccer ball, which is approximately 0.43 kg (2).
To find the force of the ball acting on the net, let the time of the ball travelling be 2.0 secondsFnet=maa=Vav/tFnet=0.43(30/2.0) = 6.45NTherefore, the ball should have exerted enough force to move the net backwards with the exact amount of force from when the ball hit the net if it were to apply to Newtonâ€™s third law which states that “for every action, there is an equal and opposite reaction.”(3) Instead the ball stayed spinning and the net did not look like it was moving at all.In real life, if the ball were to hit the net with the amount of force that Sing exerted, the net would have thrashed violently and the ball would have hit the ground immediately right after because of the force of gravity acting on the ball.) When another guy throws a soccer ball at Steel Leg, he kicks it back to him with tremendous force.
The ball hits the man in the stomach, propelling him backwards, into a roll, and continuing to slide for a couple of feet. From the far shot, one can estimate that the 160 lbs man flew about a total of 30 feet. Its a little hard to tell the acceleration from the film because the shaky camera follows the man flying, but the background moves about roughly about 7 inches per frame, being about 10 mph. The force exerted from the ball looked like he got hit by a train. Somehow in the next scene, the ball is seen moving horizontally when Steel Leg jumps up into the air and kicks it downward. The ball curves and hovers over the ground, ripping apart large chucks of grass, dirt, and its so powerful that it pulls the thunderclouds in. The ball cyclones and carries people in its vortex, and as the goalie sees it coming, it rips off his clothes and carries everything into the goal, destroying its posts. According to destruction path of the end shot, the goal was made from 3/4ths of the field.
There is one action that is concurrent with real physics: when masses are unequal, the momentum of the smaller mass can multiply via a slingshot effect; however, the power to generate such a force as to change weather must have had some kind of impact on his leg. The reason you cannot do those things is because of the theories of force and momentum. Use the newtain laws for force to explain why you can’t do that. The equation is F=m*a which is force equals mass times acceleration. The reason that you can’t knock a person over with a soccer ball is because it doesn’t have a substantial amount of mass and that no matter how much force you put into the soccer you won’t knock a person over a just 20 feet acceleration formula is a= V/t which is the change in velocity over time.
So the father it is the faster the acceleration, for example if I fire a soccer ball 100 yards away from a person from a cannon I’ll definitely knock that person down because of the force increase so the momentum increases. The momentum formula is P=F*d which is momentum equals force times distance so that’s why it couldn’t knock anyone over because it couldn’t have generated enough force and momentum to knock anyone down from just 20 feet from a human kick, the kick doesn’t even generate a enough force to gain enough force to knock a person down.
Now for the 20 foot jump in the air, have you ever heard the gravitational constant be 9.81 m/s^2.It is the average cal. constant for gravity on Earth. There is no way a human can jump that high because Fg=G(m1*m2)/r^2 this means the force of gravity equals the universal gravitational constant (which 6.663*10^-11) times the mass of the object times the mass of the planetary object(the mass of Earth is 5.874*10^8)divided by the center of distance squared. The person that’s trying to jump that high must have a stronger force upward than the force of gravity downward. To achieve this the person would have to had lived on a planet at least three times the gravity of Earth(let’s say 1g=9.81N).Multiply that by three and they’ll be able to jump 20 feet in the air, but since that’s highly improbable that’s impossible. Due to his Shaolin Training, he is able to kick the ball so high that it disappears from the naked eye and stays in the air for over an hour.
When the ball hits the ground, it exerts its force on the ground, which is such a large mass that it does not move but exerts a reaction force onto the soccer ball, causing the soccer ball to bounce back into the air. The soccer ball loses some energy from friction, but reaches no more than 12 feet in the air and stays in the air for less than 2 seconds on the second bounce. The soccer ball is an elastic object with an estimated coefficient of restitution of height loss to be between 40%-60% with each bounce. Even if the soccer ball bounce was calculated at the higher height loss of 60% per bounce, with this calculation it would mean the first kick only reached 30 feet height (12ft / 0.4) and stayed in the air for 5 seconds (2sec / 0.4). This was obviously not the case, as the ball was portrayed to have stayed in the air for over 60 minutes. This inconsistency demonstrates that the shaolin powers of the “Mighty Steel Leg” applies only to the initial force exerted on an object but loses its power in the reaction force.
In another example, when the Shaolin Soccer Team goes against the Demon Soccer Team in the finale match, the Action-Reaction Principle is overpowered by the power of “American Drugs” for the Demon Team athletes. When Mighty Steel Leg attempts his third goal at the Demon goalie, the CGI portrayed the ball to travel about 15 inches per frame, which is estimated to be 20 mph. The CGI special effects portrayed the soccer ball to break through the atmosphere, changing the atmosphere colors into the shape of a Puma, indicating its high speed.
The Demon goalie not only stopped the ball, he grabbed it with both hands without bending his elbows or moving any other parts of his body. Although the ultra-fast soccer ball appeared to cause no damage to the goalie, the impact of the soccer ball seemed to cause the reaction force to exert from the goalie’s feet onto the ground around him. The CGI portrayed the reaction force to cause an outward circle of energy in the form of the ground rippling and the wind blowing around the goalie. This is another example of special Action-Reaction Principles in the Shaolin Soccer Animation when it comes to strong characters. .