It would not be wrong to say that physics is the most important branch of science in making sense of our life. In addition to this, it is really an endless field that still encompasses many unknowns. Recently, we came across a video that we saw on Twitter and couldn’t predict whether it was physically possible or not.
In the video in question, the propeller of a flying helicopter appears as if it is not moving. The share owner made the following note as a description of the video: “This is what it looks like when the frame rate of the camera and the helicopter blade is synchronized.”
It is quite natural to be skeptical of this video, which at first glance seems impossible. After all, how can the propeller that will lift this heavy vehicle stand still? We held a magnifying glass to the scientific background of this and thought we would share our findings with you.
The speed of the propeller and the frame rate captured by the camera per second is the same
First of all, let’s look at how the cameras transmit the image to us in order to better understand the issue. The recording style of the modern cameras we use today changes according to the model and equipment. However, the basic principles he uses for recording motion pictures are the same. A moving image is formed by many images flowing very quickly. Our brain cannot capture these fast-flowing frames one by one and therefore sees them as moving. This is simply how we can describe the technology of recording images.
Of course, there are explanatory images of how this works. The video, in which British photographer Eadweard Muybridge recorded a racehorse and a jockey on it, is the first experimental work known today in the history of cinema… Muybridge had succeeded in obtaining a moving video by turning the 12 photos he had added one after another with the help of a wheel.
Here are the moving images that started the world cinema adventure:
Muybridge’s motion pictures were of course rather primitive because they were experimental. It was not possible to talk about cinema until the Lumiere Brothers’ movie called “The Arrival of a Train at La Ciotat Station”, which reveals modern cinema today. As a result, we can say that these moving images are composed of still frames, one after the other. Today, ’24’ still frames are shown in one second in modern cinema and we call all these scenes ‘film’.
Lumiere Brothers’ First Movie:
Let’s come to this helicopter video… First of all, since the frame per second (FPS) recorded by the camera is high, the speed of the helicopter’s propeller catches up. Therefore, since the speed of the camera and the speed of the propeller are equal, we see it as if it is not moving.
To understand this better, let’s consider two cars moving side by side at ‘the same speed’. Let a cameraman in one of the cars record the other car through the window. When we look at the recording, we see that the recorded car does not move, does not move forward. Because both vehicles are traveling at the same speed.