The car starts to brake at the speed of 10m / s, the acceleration is 2m / S2, and the displacement ratio of 3S, 2S and 1s before stopping is calculated
Reverse thinking: displacement ratio of 3S, 2S and 1s before stopping = uniform acceleration linear motion with initial velocity of 0, displacement ratio of 3S, 2S and 1s before starting motion = 5:3:1
RELATED INFORMATIONS
- 1. When a car moves forward at a speed of 10m / s and the acceleration is 2.5m/s2 after braking, what is the displacement in 3S? What is the displacement within 10 seconds after braking?
- 2. A car moves forward at a constant speed of 10m / s. after braking, the acceleration is 2.5m/s and the displacement within 3S
- 3. A car stops and starts to run at 3 meters per second, when a bicycle comes at a constant speed of 6 meters per second How long does it take for the car to catch up with the bicycle? What is the distance between the two cars?
- 4. If the average speed of a moving object in the first second is 3m / s, the average speed in the second and third seconds is 6m / s, and the average speed in the fourth second is 5m / s, then the average speed of the object in the first two seconds is? The average speed in the whole time is?
- 5. One student finished half of the course at 3m / s, and immediately finished the other half at 5m / s______ m/s.
- 6. The width of the river is 300 m, the flow velocity is 3 M / s, and the velocity of the boat in still water is 5 m / s, Q: (1) what is the shortest time to cross the river? Where can I get to the other bank? (2) Where should the bow of a boat cross the river on the shortest voyage? What is the crossing time?
- 7. If the speed in the first half of the journey is 5m / s, and the speed in the second half of the journey is 3m / s, the average speed of the whole journey can be calculated In a hurry
- 8. When an object moves in a straight line in a period of time, the velocity V1 in the first half of the time is 5 m / s, and the velocity V2 in the second half of the distance is 3 M / s What's the average speed of this object over the whole distance
- 9. When someone is riding a bicycle, the average speed on the uphill is 3m / s, and the average speed on the downhill is 5m / s
- 10. A's speed is 5 m / s, B's speed is 3 M / s, in the same direction, if a let B for 4 s first, how many seconds does a run to catch up with B?
- 11. The average speed in the third second is 9 m / s. find (1) the acceleration of the uniform deceleration of the car (2) the displacement of the car in 10 s
- 12. When a bus comes into the station, it starts to brake and make a uniform deceleration linear motion. The displacement in the first second and the second second is 9m and 7m respectively, then the displacement in the sixth second after braking is () A. 20 mB. 24 mC. 25 mD. 75 m
- 13. Because of the brake, the car starts to make uniform deceleration linear motion at the speed of 10m / s. if the average speed in the first second is 9m / s, what is the displacement of the car in the first 7S?
- 14. After entering the station, the car starts to brake and decelerate in a straight line. In the first second, the displacement is 9 m and 7 m respectively After entering the station, the car starts to brake and make a uniform deceleration linear motion. The displacement in the first second is 9m and 7m in turn. Then what is the displacement in the sixth second after braking? Why can we use the displacement difference 2m to get 9,7,5,3,1,0m? Why is it 0m in the end
- 15. After braking, the car moving at a uniform speed of 10m / s moves in a straight line with uniform deceleration. The displacement within 2S after braking is 6.25m, and that within 6S after braking is 6.25m
- 16. If the displacement is 6 meters in the first second and 2 meters in the last second before stopping, then: (1) during the whole deceleration If the displacement in the first second is 6 meters and that in the last second before stopping is 2 meters, then: (1) what is the displacement of the car in the whole deceleration process? (2) how much time does the whole deceleration process share?
- 17. What is the displacement ratio of a car moving along a straight line after braking, decelerating and taxiing evenly and stopping in 3.5 seconds
- 18. If the displacement in the second second second after braking is 6.25m (the braking time is more than 2S), then (1) what is the acceleration of the vehicle? (2) What is the displacement of vehicle passing through in 6 seconds after braking?
- 19. After braking, the moving car moves in a straight line with uniform deceleration and stops in 3.5 seconds. The ratio of the displacement that it passes in 1 second, 2 seconds and 3 seconds after braking is () A. 1:3:5B. 3:5:7C. 1:2:3D. 3:5:6
- 20. When an object moves in a straight line with a uniform acceleration of 2m / s and the displacement in the second second is 12M, the initial velocity of the object is