A Ford Falcon has a maximum breaking deceleration of 1.8m/s/s. If it is travelling at 120km/h before the brakes are applied, how long does it take to stop?
+128474 Note that
120km 1000m hr
______ x _______ x _______ = 100/3 m/s
hr 1km 3600 s
We have that
Final velocity= Initial Velocity + acceleration * time
So
0 = (100/3)m/s + -1.8 m / s^2 * time
- (100/3)m/s = -1.8m/s^2 * time
(100/3)m/s
__________ = time
1.8 m/s^2
(100/3) s 100
_______ = time = _____ s ≈ 18.52 s
1.8 5.4
