A car with a uniform speed of 10m / s, after turning off the engine, decelerates with an acceleration of 4m / S ^ 2. What are the speeds at the end of 2S and 3S?

V2=V0-at=10-2*4=2m/s
Deceleration time t = V0 / a = 10 / 4 = 2.5s
That is, the car stops after 2.5 seconds, so the speed of the car is zero at the end of 3 seconds

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