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In the 100 meter race, the athlete ran 80 meters at the speed of 8 m / s, and then ran 20 meters at the speed of 2 m / s to find the average speed of the road But the answer is 5.5m/s
(80+20)/(80/8+20/2)m/s=
An athlete ran 80 meters at the speed of 8 m / s, then walked 20 meters at the speed of 2 m / s, the speed of the athlete passing this section of the road
v＝s／t＝100／10＋10＝5m／s
How to improve 100 meter speed
All kinds of ball games; (1) push the ball with both hands → then start to catch the ball; (2) throw the ball forward with both hands → then run out to catch and catch the ball; (2) all kinds of game response exercises; (3) push the starting device to start or listen to the signal (password, applause, etc.); half squat posture, listen to
It takes 12 seconds for a student to take part in the 100 meter race. The speed at the midpoint is 10 meters per second. Ask him to run the 100 meter race
It takes 12 seconds for a student to take part in the 100 meter race. The speed at the end is 10 meters per second
It's really a requirement. You don't need to look at the terminal speed in the back
The speed changed in 100 meters, but it took 12 seconds to get there
Average speed = distance / time
100m/12s=8.33m/s
This should be the physics of senior one, right?
If you are a freshman in senior high school, the title is very simple
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