Why kicking a soccer ball from the middle of the soccer ball doesn t spin

If the force point is wrong, if the direction of force passes through the center of gravity, it does not rotate, in the jargon, it is the Magnus effect

A phenomenon in fluid mechanics is the force exerted on an object (such as a cylinder) rotating in a fluid.

When the rotational angular velocity vector of a rotating object does not coincide with the object's flight velocity vector, a transverse force will be generated in the direction perpendicular to the plane composed of the rotational angular velocity vector and the translational velocity vector. The phenomenon of deflection of the flight trajectory of an object under the action of this transverse force is called the Magnus effect. The reason why a rotating object can produce force in the transverse direction is that the rotation of the object can drive the surrounding fluid to rotate, so that the fluid velocity on one side of the object increases and the fluid velocity on the other side decreases.

According to Bernoulli's theorem, an increase in fluid velocity will lead to a decrease in pressure, and a decrease in fluid velocity will lead to an increase in pressure, which will result in a pressure difference in the transverse direction of the rotating object and a transverse force will be formed. At the same time, since the transverse force is perpendicular to the direction of motion of the object, this force mainly changes the direction of flight speed, that is, the centripetal force in the motion of the object is formed, thus causing the change of the direction of flight of the object. Using the geopotential flow theory, the flight motion of a rotating object can be reduced to the motion of a "straight uniform point vortex dipole", where the point vortex is the source of the formation of lift.

In the two-dimensional case, the transverse force of the flow around the rotating cylinder can be calculated using Jukovsky's theorem, i.e., the transverse force is the flow velocity x fluid density x the amount of vortex rings at points.

Dizzy! The direction of force does not rotate through the center of gravity.

The Magnus Effect! Be specific to yourself!

Why don't you ask the physics professor?

The force is concentrated on one point, of course, it does not turn.

Hehe, it's very simple, the force part is the middle of the ball. It is equivalent to the force on the center of gravity of the ball, and it will definitely not turn when kicked out. When the strength is great, there will be irregular movement, and Ronaldo lifts the ball.

This is what ordinary people do, but not ordinary people can!

I thought that a family of three would hate her from now on, hate her to the bone, and take it into account.

The way football can turn is commonly known as banana ball, which has the same curve as bananas. The principle is that when an object is moving in the air, the side with the fast air velocity has less pressure. The banana ball of football is rotated after being kicked out, resulting in different pressures on both sides of the ball, so the trajectory is not straight (other balls also have this phenomenon, such as table tennis balls called curveballs), as for why the air velocity will cause the pressure to be different - it seems that the knowledge before junior high school has been returned to the teacher.

The method of kicking the spinning ball in football: the habitual foot is the right foot as an example, and the internal rotation is to rub the lower right quarter of the ball with the silver wheel bow of the foot, the greater the power, the stronger the rotation, pay attention to the rotation only at a long distance to sharpen the disadvantage is obvious; External spin, on the other hand, kicks the left half of the ball with the right instep, and the greater the force, the greater the spin. But the key is to practice on your own, just practice more.

Soccer is a ball game, and it also refers to the ball used in the game, but here it represents the former. Ancient football originated in China, and Tongli modern football originated in the United Kingdom and is considered the number one sport in the world and the most influential single sport in the global sports world.

On the one hand, the air flows backwards towards the ball, and on the other hand, the air around the ball will rotate with it due to the friction between the air and the ball, and the direction of rotation of the ball is the same as that of the ball, and the velocity of the side with respect to the air is smaller than that of the other side. Physics tells us that the higher the velocity of the gas, the lower the pressure.

Since the air flow speed on both sides of the football is different, the pressure generated by them on the football is also different, so the football is forced to turn to the side with a high air flow speed under the action of air pressure.

Copying someone else's, sin, sin ......

Relative to the ground, the ball is panning; If you look at the football alone, the football is spinning. Football is a sport in which the feet are the main thing, controlling and dominating the ball, and two teams attack and defend each other on the same rectangular field according to certain rules.

Because of its strong confrontation, changeable tactics and large number of participants, football is known as "the world's No. 1 sport".

In formal football, the playing field shall be rectangular and shall not be more than 120 meters or less than 90 meters in length and 90 meters in width and 45 meters in width (the length of the field shall not be more than 110 meters or less than 100 meters and the width shall not be more than 75 meters or less than 64 meters in the international competition). In any case, the length must exceed the width.

On the goal line at both ends of the playing field from the goal post at the inside of the goal post, draw a long meter perpendicular line to the goal line to the field, one end is connected with the goal line, and the other end draws a connecting line parallel to the goal line, and the area within the range of these three lines and the goal line is called the goal area.

A regular football match lasts 90 minutes and is divided into two halves, each of which lasts 45 minutes. The break between the first and second halves shall not exceed 15 minutes. There is one referee and two touchline referees in the game, and in each half, the referee can make up time depending on injuries and substitutions on the field.

If the match must be decided, a penalty kick will be awarded if the two teams are tied within 90 minutes, with a difference of 15 minutes of extra time in each half, and a penalty kick if the match is still drawn.

Decide the winner.

It is a curved ball, commonly known as a banana ball, which changes the trajectory of the ball because the ball is kicked from different positions and causes the ball to spin rapidly.

Curveball. It is kicked out by rubbing the ball with the inside test or outside of the foot. For example, the shell arc.

Very famous. It's easy to kick a curveball. But it's hard to figure out where to kick which IU.

It takes a lot of practice. Hehe.

This question is not clear, if it is kicked with the right foot, and it is kicked out with the inner instep, because the force is forward, and the ball is counterclockwise because the force is counterclockwise, so it also rotates counterclockwise, if it is kicked with the outside instep, it becomes clockwise, and the left and right feet kicked out and the inner and outer instep kicks out have different effects!

If it's about atmospheric pressure, that's not a matter of direction of rotation, the right foot inside kick and the left foot outside kick can make the ball rotate counterclockwise, I remember junior high school also encountered this problem, I prefer football combined with physics is that it not only rotates and the most important thing is that the rotation has an "arc" is the key, the ball turns counterclockwise on its left side of the air flow rate is fast, the right side of the air flow rate is slow, the atmospheric pressure makes the football produce a rightward arc, with the decrease of the force The arc gradually decreases. This is actually the same as when an airplane takes off.

Because it seems to be in line with IFSRDR, there is a place to start up** and formed.

On the one hand, the air flows backwards towards the ball, and on the other hand, the air around the ball will rotate with the ball by the friction between the air and the ball, and the direction of rotation of the ball is the same as that of the ball, and the speed of the air on one side is smaller than that on the other side. Physics tells us that the higher the velocity of the gas, the lower the pressure.

Since the air flow speed on both sides of the football is not the same, the pressure they exert on the football is also different, so the football is forced to turn to the side with a large air flow velocity under the action of air pressure.

Copying someone else's, sin, sin ......

In this question, under the condition that the magnitude of the force remains unchanged, the effect is not the same, mainly because the effect of the force is different and the direction of the force is different, which will lead to different effects

Therefore, the answer is: the point of action of the force, the direction of the force