If an object moving in a straight line with uniform velocity changes 6 m in the second second, and the displacement is 0 in the fifth, what is its initial velocity and acceleration? Let the direction of the initial velocity be the positive direction. I've previewed it, but some haven't learned it

Using a small conclusion: in the uniform variable speed linear motion: the instantaneous speed in the middle is equal to the average speed in this period of time
Therefore, it can be seen that the speed at the end of 1.5s is 3m / s after walking 6m in 2S
The displacement in 5S is 0, so the velocity at the end of 4.5s is 0
A = v2-v1 / (t2-t1) = - 3 / 3 = - 1
Using the velocity formula to calculate the initial velocity

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