You are driving through town at 12m/s when suddenly a ball rolls out aim front of you. You apply the brakes and begin decelerating at 4ms^2. How long does it take you to stop?
The answer I got is -3 is that possible!!!!??! I'm not sure what doing wrong.
vf^2=vi^2 + 2ad that will give you the distance.
vf=Vi+at where a=-4 solve for t, that will give you the time.
Why is it negative 4? Is id because it's decelerating?
Yes, negative acceleration = deacceleration
change in velocity is negative
Thank you!!!!!!!!
You are welcome :)
It seems like you may have made an error in your calculations. Let's go through the problem step by step to find the correct answer.
Given:
Initial velocity (u) = 12 m/s
Deceleration (a) = -4 m/s^2 (negative because you're decelerating)
Final velocity (v) = 0 m/s (since you have stopped)
We can use the equation of motion to find the time it takes to stop:
v = u + at
Rearranging the equation to solve for time (t):
t = (v - u) / a
Plugging in the values:
t = (0 - 12) / -4
t = (-12) / (-4)
t = 3 seconds
Therefore, it takes 3 seconds for you to come to a complete stop. It's important to ensure that you consider the negative sign when plugging in the values, as deceleration is represented by a negative value.