A car begins decelerating at 2 m/s2 and takes 30 meters to stop. How long did the car take to stop?≈ 5.5 s≈ 7.5 s ≈ 4.5 s≈ 8.5 s

To solve this problem, we can use the equation of motion: v^2 = u^2 + 2as, where:

v = final velocity = 0 (since the car stops) u = initial velocity (which we need to find) a = acceleration = -2 m/s^2 (negative since it's deceleration) s = distance = 30 m

Substituting the known values into the equation, we get:

0 = u^2 - 2*30 u^2 = 60 u = sqrt(60) ≈ 7.75 m/s

Now, we can use the first equation of motion to find the time: v = u + at, where:

v = final velocity = 0 u = initial velocity = 7.75 m/s a = acceleration = -2 m/s^2 t = time (which we need to find)

Substituting the known values into the equation, we get:

0 = 7.75 - 2t 2t = 7.75 t = 7.75 / 2 ≈ 3.875 s

So, the car took approximately 3.875 seconds to stop. However, this option is not available in the choices given. It seems there might be a mistake in the problem or the choices.