You can imagine a falsetto or mixed voice easily if you know and understand how to control/move the vocal cord mucosa.
Please see here about vocal fold.
Here are some key points :
The vocal cord mucosa can change its figure & flexibly, but never by itself. It can change only by exogenous forces and the internal capacity changes nothing.
I will explain how by demonstrating with Konjac foods and a hair dryer.
This experiment is using konjac foods as a comparative example of the vocal cord mucosa surrounding the vocal chord. Konjac is a food made from the root of a plant, which is widely known in English by its Japanese name, konnyaku (yam cake), being cooked and consumed primarily in Japan. The two basic types of yam cake are white and black. Pushing the cake through a grid of sharp blades at the end of a wooden box creates noodles, called shirataki, which are also sold in white and black colors.
For this experiment, I sliced the konjac thin, and placed each one parallel to eachother, mimicking the vocal cord mucosa. Being minful of gravity and needing to reenact air and wind as an example of the airflow used to create voice, I chose a hair dryer.
I then proceeded to use the hair dryer, to blow the surface of the konjac precisely, and then recorded this. Reviewing it in slow and paused motion.
I conducted the experiment several times, and came up with the following results.
This is rough sketch drawing displaying the movement of the vocal cord mucosa.
This picture shows the side of the horizontal surface, red is vocal muscle and pink is the vocal cord mucosa. The arrows distinctively show which direction the air flow was originating from.
1:The vocal fold closing.
2:The vocal fold is flipped up by the exalted breath, causing the apical point to go up.
3:The bottom of mucosa moves forward.
4:The top moves backward and the bottom swells in the middle.
5:The top and bottom are supposed to return to the original position. The exalted breath affects the vocal fold return to the original position more at this time. This is i referred to as “Bernoulli’s Theorem.”
Bernoulli’s Theorem is when an increase in the speed of fluid occurs simultaneously with a decrease in pressure. Bernoulli’s principle can also be derived directly from Newton’s 2nd law. If a small volume of fluid is flowing horizontally from a region of high pressure to a region of low pressure, then there is more pressure behind than in front. This gives a net force on the volume, accelerating it along the streamline. In conclusion, if fluid is flowing horizontally and along a section of a streamline, where the speed increases it can only be because the fluid on that section has moved from a region of higher pressure to a region of lower pressure; and if its speed decreases, it can only be because it has moved from a region of lower pressure to a region of higher pressure. Consequently, within a fluid flowing horizontally, the highest speed occurs where the pressure is lowest, and the lowest speed occurs where the pressure is highest.
This movement is can be varied considering the muscle size,thickness, and hardness.
If the vocal muscle is soft, it improves the vocal cord mucosa. Causing it to move more freely and making it easier to achieve complex movements, resulting in a rich tone. However, if you cannot control flexibly, it will be a difficult task to achieve and create rich pitches/tones.
If the vocal muscle is hard or rigid, expect these outcomes: Being unsuccessful in creating the pitch of a Passaggio, a Falsetto pitch will be thin/flat, and finally … not being able to combine the two, creating a mixed voice.
Take this knowledge and apply it, to understand and learn the movements of the vocal chords and the tissues that function and surround them.