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A professional badminton player can hit the badminton directly into a watermelon with a hard hit inside.
Why does a badminton with a mass of only 5 grams have such a lethal power?
The key is speed! The speed of a good professional athlete can exceed 300 km/h (approximately 83m/s) in an instant of , and has a great impact in a very short distance.
What is the concept of 300km/h? At present, the speed of the domestic G-headed motor car is also the head-up speed of the Boeing 737 aircraft. When an ordinary family car is on a high speed, it is impossible to reach a speed of 300km/h. . .
Badminton hits the watermelon, this is nothing, after all, there is a kid on the Internet who can still throw cards (flying card stunt) into the watermelon with his hand;
But in the next animation, you You can see Lin Dan smashed the board with a badminton shuttlecock, and broke the badminton racket and shuttlecock. Look at the surprised eyes of the stars, you can imagine the power of Lin Dan's racket! It is reported that this board is 12mm thick.
Because the air has a great resistance to the badminton and its own mass is too small, the speed of the badminton is also very fast after being separated from the racket. Therefore, usually people do not think that badminton can achieve Such a great speed.
The top speed of a badminton smash is 426 km/h, This record is the men's doubles player Coding from Denmark hit a 426 km/h smash in 2017, breaking Li Zongwei in one fell swoop The world record for the fastest scoring by a male player of 417 kilometers per hour.
and Lin Dan’s current top speed of smash is said to be 401 km/h, ranking fifth in the world; and the smash in the show is by no means the highest level, so It is conceivable that the maximum lethality of badminton smash per hour will be much?
How much is the lethality of the badminton
The energy of an object due to its movement is called the kinetic energy of the object. Its size is defined as one-half of the product of the mass of the object and the square of the velocity.
Calculated like this, the kinetic energy of the badminton Ek=0.005*83*83/2=17.22J (in fact, this calculation is meaningless, and the kinetic energy is finally converted into Internal energy, randomly transmitted to the surrounding environment)
We can change the concept and think from the perspective of the momentum theorem. The momentum theorem is that the increase in the momentum of an object is equal to the impulse of the external force it receives, namely Ft=mΔv, and the badminton moves 300 km/h until the impacted object is stationary, we assume that the time is 0.01s, at this time we can calculate the impact force between the badminton on the object in this process; F=mv/t=0.005x83/0.01 =41.5N
Wrong, can 41N force crush the wood board? Obviously not, but we ignore the action area, that is, 41N force acting on a small area will produce a lot The pressure;
Then let's calculate, how big is this pressure probably?
The diameter of the badminton cue is 25 mm to 28 mm, and the bottom is circular. The projected area of the badminton head is S1=πr2=3.14x(0.025*0.025)=0.0019625m2
Because the badminton head is a sphere, At the moment when the badminton head hits the board, we assume that half of the head’s projected area is in contact, so S=S1/2 we calculate the pressure as P=F/S=41.5/(0.0019625/2)pa=42293pa=0.0423Mpa
What is the concept? The pressure of tap water is 0.14Mpa. According to the theory, this pressure is not enough to calculate the plank. I don't know whether it is a problem with the calculation or the program effect. . .
Everyone is welcome to add in the comments that you think there are some incorrect or missing parts in the article, so that the next reader will learn more, and you know exactly what everyone needs. . .
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