# A car moves with a speed of 80 m/s. If the driver used the brakes to decrease the speed, so it decreases by 2 m/sec^2. What is its speed after 12 seconds from using the brakes?

##### 2 Answers

Oct 29, 2015

I found

#### Explanation:

Here you can use the cinematic relationship:

Where:

in your case:

Oct 29, 2015

The car's speed after twelve seconds of using brakes is

#### Explanation:

If the car's acceleration due to braking is

Therefore, if the car's speed is