Answer: The acceleration is - 1.8 m/s^2
Step-by-step explanation:
From the information given,
initial velocity of bike, u = 12 m/s
final velocity of bike, v = 0 because the bike came to a complete stop
distance traveled, s = 40 m
We want to find the acceleration, a
We would apply the the newton's equation of motion below
v^2 = u^2 + 2as
By substituting the given values into the equation,
0^2 = 12^2 + 2 x a x 40
0 = 144 + 80a
Subtracting 144 from both sides, it becomes
0 - 144 = 144 - 144 + 80a
- 144 = 80a
80a = - 144
Dividing both sides by 80,
80a/80 = - 144/80
a = - 1.8 m/s^2
The acceleration is - 1.8 m/s^2