When a car is running at a constant speed of 20 m / s and reaches an acceleration of 4 m / S2 after emergency braking, what is the displacement within 8 s after braking? Such as the title

The stopping speed is 0, and the time from deceleration to stopping is t
0=20-4t t=5/s
That is, the bus stops in 5 seconds
x=vo*t+1/2at²
=20*5-2*25
=50m

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