" Berserk " was a close relative of " Thorosaurus " , but it was much larger : The dinosaur had a 40-foot-long tail with a tail root that was more than 3 feet thick , but the tip of its tail was as thin as the little finger of a modern man. Such a beautiful tail tip makes its tail too fragile to attack the attacker. So what is the role of its tail? Its role may be to swing it like a whip.
About 20 years ago, the idea began to gain favor in the scientific community that the confused dragon used its tail as a whip to scare away predators, while also using it to communicate and even show off in front of potential mates. To that end, since then, paleontologists Philip Currie and Nathan Myhrvold at the University of Alberta in Canada have devised a computer model to prove that this explanation of using the tail as a whip works.
Recently, at a conference on vertebrate paleontology in Melward, Currie et al. demonstrated a 1/4 scale physical model of the tail of a confused dragon made of aluminum as a vertebra and steel as an tendon.
Considering the strong thrust of the root of this tail model, it can make a cracking sound when it is swung in the air. The analysis of the high-speed video model shows that the tip of its tail can move more than 800 miles per hour — enough to break the sonic barrier and produce small-scale sonic booms. When an adult confused dragon swung its tail like this, its sound was extremely high enough to pierce the eardrums of humans.
The crackling sound of the whip is the whip breaking through the sound barrier
With circumferential movements and human labor alone, it is almost impossible to bring the whip to supersonic speed. The length of the whip is 2 meters, and to make the end supersonic, it needs a speed of 27 revolutions per second, and the manpower may not be able to reach it. However, when you suddenly stop the handle while turning, the various microsections of the whip will stop sequentially, and its kinetic energy will be passed to the next microsection, that is, the next segment will accelerate, and finally the kinetic energy of the whole whip will be concentrated at the end, and its mass is quite small, according to E = 1/2 mv^2 can be obtained v tends to infinity.
Of course, in fact, limited by air resistance and internal friction of the whip material, the speed is limited, generally can reach about 2 times the speed of sound. In fact, all rope-like objects have this effect, throwing towels, shaking clothes, can make a sound, but because the kinetic energy is small, can not reach the speed of sound, so the sound is not large and low (at this time, the vibration sound after the object is tensioned).
Nylon rope is theoretically ok, but because the unit mass of nylon rope is small, it is too affected by air resistance, and the end cannot be accelerated to the point where it can make a pronounced sound.