The car drives past the observer, moving at a speed of 10 m / s. At this moment, the driver presses the brake

The car drives past the observer, moving at a speed of 10 m / s. At this moment, the driver presses the brake and the car begins to move with an acceleration modulo 1 m / s2. How long will it take until the car stops?

By the condition of the problem:

v0 = 10 m / s, vehicle speed;

a = 1 m / s ^ 2, the acceleration of the car after the start of braking;

It is required to find t, the time that the car will travel to a stop.

It is also clear that:

– at the moment of stopping, the speed v1 of the car is 0;

– since the car is braking, acceleration is directed against the movement, that is, it is taken with a negative sign.

We find the time by the formula:

t = (v1 – v0) / a = 0 – 10 / -1 = 10 s.

Answer: it will take 10 seconds for the car to stop.