Answer:
The time interval is
![t = 6.667 \ s](https://img.qammunity.org/2021/formulas/physics/college/d7eaj0nle6a00a2m2vj4uowqfabr36yx4l.png)
Step-by-step explanation:
From the question we are told that
The acceleration of the car is
![a = 3 m/s^2](https://img.qammunity.org/2021/formulas/physics/college/qpe3exqahg6qcr00nqgzy1hekhl4z46ett.png)
The velocity of the car is
![v= 20.0 \ m/s](https://img.qammunity.org/2021/formulas/physics/college/344czv3i89imuuao7vg6qiowmryw6dzf9d.png)
The final velocity of the car can be mathematically represented as
![v =u + at](https://img.qammunity.org/2021/formulas/physics/college/cq0jm14s8nch4pht3i437cgddu8xkvpbeb.png)
Now since the car start from rest u = 0 So
![v = 0 + at](https://img.qammunity.org/2021/formulas/physics/college/q14m7cb1wli77k4kiky66zy9x1pxok8fl3.png)
![v = at](https://img.qammunity.org/2021/formulas/physics/college/rvomti47yrc0j2xkamghgxg6irl99m3lga.png)
substituting values
![20 = 3 t](https://img.qammunity.org/2021/formulas/physics/college/h7vr5smo9d1t0qv1ykvofgw37mppbi9cbc.png)
![t = (20)/(3)](https://img.qammunity.org/2021/formulas/physics/college/pzmnqkhmq3iuqg1tbr1oqycffmlvlenes5.png)
![t = 6.667 \ s](https://img.qammunity.org/2021/formulas/physics/college/d7eaj0nle6a00a2m2vj4uowqfabr36yx4l.png)