Poor Physics #1

Motorcyclist goes flying through a windshield from inside of a truck

In this scene, a motorcyclist pursuing Lee and Carter pulls his motorcycle tries to avoid hitting a green bin, hits it and goes flying up. The motorcyclist goes flying (projectile motion) in an arc and into the open back of a truck. He then goes flying UP through the windshield into the windshield of a parked car.

     If you pause the scene at 0:04 seconds you can clearly see that he goes flying up.

     When he goes flying UP through the windshield it is an example of bad projectile motion. When the cyclist is in the truck he would hit the seats and go flying because of Newton's First Law (Newton). However, his upward motion starts far from the windshield so he should not go flying UP through the windshield. He should fly straight out, down, or not through the windshield at all. The initial speed of the motorcyclist in the truck would be slower considering he would not want to "die". Due to the reduction of the speed he would reach his max height at a lower point than if he traveled at a higher speed. He should not have gone UP through the windshield. If he did travel at a higher speed while he was in the truck, when he started his projectile motion he would have flown too high up when he reached the windshield and would have hit the ceiling of the car. Also, notice how the windshield comes out of the truck WHOLE if the motorcyclist can hit the car's windshield and create a spiderweb of cracks, why is it that a whole windshield come out untouched? He would have either gone through it, shattered it, cracked it, but he would not have pushed it out whole. Therefore, this scene was  an example of bad usage of projectile motion. 

     In reality any one of the illustrated instances should have occurred instead of what did occur.

The motorcyclist flies through the window, but not UP.

The motorcyclist never hits the window.

The motorcyclist hits the ceiling and falls back down.

Poor Physics #2

Lee and Carter parachute down Eiffel Tower 

In order to escape from their pursuers, Lee and Carter take a French flag and use it as a parachute to come down from the tower. However, their pursuers shoot at the flag, creating numerous holes in it. This causes them to fall quicker. Because of the “wind”, Carter and Lee are pushed forward and they land in the fountain safely.

When we look at the motion of the parachute falling by itself, it makes sense since the “wind” creates lift and pushes them safely down the tower. However, as they are landing, a fountain that is shooting up water is present. Notice how the water falls down nearly straight down. If the “wind” was blowing Carter and Lee at the speed it was supposed to be, the fountain water would be falling down at an angle due to the same force from the “wind”. But, there is no evidence based on the fountain that there is such wind that could push two people down in a parachute. The parachute and the fountain both have to be affected by the external force, the wind. In the movie, the parachute is gliding due to lift, stating that there is an external force, while the fountain is not affected by anything, contradicting to what the parachute is showing. Therefore, two things do not match, making it a scene with poor physics.

Poor Physics #3

Car tilts and stays tilted by balancing on motorcycle

Lee and Carter drive away from their pursuer with the help of their handy taxi driver, George, realizing that they are being chased. Being preoccupied for a brief moment, George fails to notice a man pushing a cart full of wooden merchandise. But just in time, George steers to the right, keeping it titled while Lee and Carter fight off their pursuer. 

There are visible parts in this scene that are impossible in real life. First of all, after the car tilts by trying to miss the cart full of wooden merchandise, the car should have gone back to its original position. This is because of the center of gravity of the car and the weight distribution in the car. The car’s center of gravity is positioned slightly towards the driver’s side since there more people on the driver’s side than the other (Lee and George against Carter). Since the car is heavier on the side where there are more people, it shouldn’t have stayed tilted that long. Also, the car ends up moving while being balanced on a motorcycle. Say that it is possible to even get into that situation in reality. When the motorcycle gets kicked out by Lee later on in the scene, the car should have gone off balance and went onto its side. It is like when a person is leaning on a chair, having his body's balance purely dependent on the chair. When the chair suddenly disappears like the motorcycle in the scene, the guy would lose balance and fall. So, after the motorcycle is gone, the car should have fallen to its side like the guy in the example. In addition, the car moves back to its original position after George shifts his weight to the side. While Lee and Carter were fighting, the weight distribution would have been disrupted, so if shifting the weight to the side would have made the car back to its original position, it would have occurred while they were fighting and moving about (even more so since one of the pursuers were also partially in the car on the already heavier side). It shouldn’t just go back when George wants it to. Therefore, this scene is an example of poor physics because of the car staying tilted in the first place and still staying tilted even after its support is gone, only going back when George moves slightly.

Assuming that all three men are roughly the same mass (m), we can show that because there are two people(f2) on one side (the elevated side) and one (f1) on the other that the force of gravity would be two times as great. Which should result in the car falling back down. However, this is not the case.

In this situation we see that the car is balanced on the motorcycle. The motorcycle is supporting the weight of the car. Because the car is leaning on the motorcycle, if the motorcycle were to be removed the car would fall down in the direction of where the motorcycle used to be.

Good Physics #1

Motorcyclist goes flying after hitting a green bin

In this scene, a motorcyclist pursuing Lee and Carter pulls his motorcycle tries to avoid hitting a green bin, hits it and goes flying up. The motorcyclist goes flying (projectile motion) in an arc and into the open back of a truck. He then goes flying UP through the windshield into the windshield of a parked car.

    This is an example of Newton's First and Second law (Newton) acting in accordance with each other as well as projectile motion. The motorcyclist hits the bin, because of Newton's first law he continues his motion instead because of the second law he travels upwards since he drew his motorcycle up. He starts his upward motion and goes flying up until he reaches his maximum height and he begins his descent.

Good Physics #2

Lee pulls on a flag and Carter and a gunman falls

After getting Soo-Young safely down the tower, Lee and Carter stay behind to fight the gunmen. Lee realizes that Carter and a gunman is fighting on a French flag that Lee pulled down before, so Lee pulls on the flag causing them to fall in order to distract the fight.

Lee yanks the flag out so the people on it could lose balance and fall. This is an example of the first law; the law of inertia (Newton). When the do fall, they land on the same spot from where they were standing, regardless of how the flag was swiped out from underneath them. The law states that ‘if there is no net force acting on the object (the people), it will maintain its state of rest or constant velocity’ and inertia is the ‘resistance of the object to change its state of rest or motion’. When the flag is pulled away, the flag moves away from its initial spot whereas the people continue in their state of rest; they don’t move from the spot they were in before, though, they do fall due to their loss of balance.

It is similar to when you could yank a tablecloth from underneath bunch of cutleries. With the right amount of force and angle, you can succeed in pulling the cloth out without upsetting them. This shows you that the cutleries stayed at their initial spot since there is no net force acting on the object itself while the cloth moved because the pulling motion was the net force acting on it. This is an example relating to how Lee pulled on a flag and still have Carter and the man stay at the same spot they were before.

Good Physics #3

Reynard falls into the fountain after he gets shot

In this clip, Reynard is shot by George. Reynard starts to walk forward and tumbles into the water creating a transverse wave.

When Reynard falls into the shallow water of the fountain, he creates a simple transverse wave. When the wave travels, it interferes with the waves created by the fountain. This results in constructive interference in the form of super crest. The waves travel in opposite direction, so after they superimpose each other, they continue on their way, getting smaller due to loss of energy.

Wave is created by Reynard's fall

Reynard's wave and the fountain's wave superimpose to create a supertrough

Reynard's wave and the fountain's wave superimpose to create a supercrest