Question

assume that the brakes in your car create a constant deceleration regardless of how fast you are going. if you double your driving speed, how does this affect (a) the time required to come to a stop, and (b) the distance needed to stop?

Answer 1

If that happens to your car and you double the speed then it will take the car longer to come to a complete stop

Answer 2

Answer:

Part a)

Time becomes double to stop it

Part b)

Distance to stop the car will become 4 times

Explanation:

Part a)

To find the time to stop the car we know that final speed is zero

so we will have

$v_f = v_i + at$

here we have

$0 = v - at$

$t = \frac{v}{a}$

Now since the speed is double

so the time to stop will also becomes double

Part b)

To find the stopping distance we know that final speed of the object must be zero

so we will have

$v_f^2 - v_i^2 = 2 ad$

$d = \frac{0 - v^2}{2(-a)}$

$d = \frac{v^2}{2a}$

since the speed is double so the distance to stop the car will becomes 4 times