There is a track and field athlete with a height of 1.70 m who is participating in the 100 m sprint competition.

The standard answer is: displacement 0.2m, speed12m/s.

The process is as follows:

1) The height of the person in the photo is the height of the real person1100.

2) The blur in the photo is caused by the motion of the object when the photo is taken.

3) The width of the blurred part of the number cloth in the photo multiplied by 100 is the actual moving distance of the number cloth, that is, 0.2m

4) When the displacement of 4)0.2m is completed within 1/60s, the speed is 0.2 * 60 =12m/s. ..

Disadvantages of the topic:

1) Topic assumption 1: Only horizontal displacement and velocity are considered, but vertical displacement and velocity are not considered. People will have vertical speed when running;

2) The title assumes that the camera is still. In fact, many times the photographer will chase after him, and the image obtained at that time may have a clear chest and unclear background;

3) It is assumed in the title that the horizontal speed of the athlete's chest is consistent with the overall speed of his body during sprint. In fact, when most 100-meter athletes hit the line in the sprint, the horizontal speed of his chest is faster than his body.

4) It is difficult to accurately measure the height of athletes in sprint posture.

5) The last question is: With the horizontal sprint speed of 12m/s, this athlete's speed should be able to win the national championship, and the national champion of 1.70m can be said to be a myth.