Science Fact or Cinematic Fiction

         Rarely do we stop to appreciate the laws of physics in our daily lives. A boy falls off his skateboard and the board keeps rolling, the law of inertia. Toss a baseball into the air and it will undoubtedly come falling back down, the effects of gravity. With as little as we pay attention to these everyday examples of how the laws of physics work around us, we certainly don’t tend to notice these same effects in the fantasy world of movies, that is not until they are played out incorrectly. These simple concepts that all human beings understand in the back of their minds are sometimes quite suddenly jolted forward when they are so blatantly ignored in the visual creation of a film. The law of inertia is one of the most frequently bent and broken rules of physics in both animated and live-action CGI films. An object in motion will stay in motion until otherwise acted upon by an outside force, unless of course you’re making a film.

         The animated DreamWorks film, Kung Fu Panda, provides many examples of this rule being bent for the purpose of dramatic storytelling. One of the most prominently ignorant scenes is one of Master Tigress. Standing atop the training facility, which is nestled high up in the mountains that surround the Valley of Peace, Master Tigress makes the decision to go after Tai Lung to try and stop him before he can even reach the valley to destroy it. She leaps from the roof of the building without a second thought and plummets down into the valley below, falling a long distance. Despite the great speed she picks up while falling, Tigress lands perfectly safe and unharmed on the roof of one of the houses. Not even one tile of the roof is knocked out of place.

According to Newton’s law of inertia, Tigress’ falling body would not stop simply because her feet met the roof. Although her body would stop moving if another force acted upon it, in this case that force is the roof of the house, the rate at which she was falling would require a much greater force to stop Tigress’ body. In reality, she would have crashed straight through the roof the house, and anything below that, until enough force was applied to stop her. In this scene, she would most likely not have stopped until her body met with the floor of the house. Additionally, if a fall such as this were done in a completely realistic manner, using the laws of physics correctly, the abrupt stop of her body meeting the ground would also kill Master Tigress, thusly giving quite a nasty turn to that scene in the film. If the filmmakers had created the scene this way, it would not have served the story well.

         Although the live-action film, The Fifth Element, takes place in the future where things like flying cars and space travel are completely ordinary, the law of inertia is still broken several times. During an important scene, Korbin Dallas is persuaded by his attractive fare, Leeloo, to help her evade police capture by taking off in his hover-taxi. A chase ensues and in an attempt to avoid bullets and being captured, he makes a sharp vertical turn at a high speed. Despite the sudden change in direction the taxi experiences no drag. Even if the car had been able to make such a drastic directional change, it would have been moving forward as it tried to pull upwards into the vertical turn. Secondarily, in the next few moments of the scene, when the vertical turn takes them up through some train tracks and the train is headed for their vehicle, the taxi takes yet another sharp left turn in which there is no effect from the inertia it had when traveling in a forward direction. In reality, the taxi should have been dragged forward here as well, and since the train was so close to hitting the car it likely would have been struck by the front of the train. It is also worth noting that the police car that was chasing them prior to the vertical turn ended up crashing through the side of a big rig truck but somehow managed to stop just inside, without crashing through completely, in spite of the high speed at which they were traveling.

         One of the best displays of inaccuracy where the law of inertia is concerned can be found in a scene from the recent 2009 film, Star Trek, during which the young James Kirk drives a car off a cliff. When the scene opens, Kirk is driving a stolen vehicle down a long stretch of dirt road when a police officer pulls up alongside him and orders him to pull over. He pulls a sharp right and busts through the gates to a restricted area of land and continues speeding along at over eighty miles per hour towards the edge of a cliff that is in the distance; the policeman is not far behind him. Within the last twenty feet before the drop, he yanks the emergency break and the car turns so it turns and skids towards the ledge. Immediately following this action, Kirk flings himself from the vehicle so that he won’t go hurtling over the edge with it.

When first viewed, there is a feeling of doubt instilled by what is seen on the screen; there’s no way a normal human being could really do this and live to tell the tale. The mind might rationalize that perhaps if Kirk knew his way around cars that perhaps he could pull it off if the action was timed right, but this just isn’t true or possible. When Kirk jumps from the vehicle, it is within reason to presume that the car is still moving close to eighty miles per hour as it barrels towards the edge, and his body continues at that speed as well, even though he’s leapt from the car. With such a short amount of space in which to jump from the car safely, and while moving at such a high speed, Kirk would plunge over the edge before his body even had a chance to drop far enough to hit the level of the ground. Even if he did manage to land on the dirt before the cliff’s edge, Kirk would still be dragged over since there’s not enough applied friction from the ground to stop him in time.

         Through all of these scenes, it is apparent that filmmakers have little issue with bending and breaking the laws of physics in both animated films, where it might be expected, and live-action films, where a certain degree of reality is expected. When breaking the law of inertia suits the story, the thought of inaccuracy might only barely cross our minds as we sit back to enjoy the cinematic efforts. And, perhaps it is too much to expect that films would at least take such a simple thing as inertia and display it accurately when we go to view these films for the purpose of being taken out of the real world. So, while the law of inertia is often inaccurately portrayed in films, it is usually done so for dramatic effect to make the scene more interesting without maiming or killing the characters involved and we can forgive these indiscretions in favor of the great stories we seek by choosing to view these movies.