Answer:
acceleration = - 150 m/s^2
distance = 9 miles.
Explanation:
initial speed, u = 60 mph
time, t = 12minutes = 0.2 hour
final speed, v = 30 mph
Let the acceleration is a and the distance is s.
By the first equation of motion
v = u + at
30 = 60 + a x 0.2
a = - 150 m/s^2
Let the distance is s.
Use third equation of motion is
[tex]v^2 = u^2 + 2 a s \\\\30^2 = 60^2 + 2 \times 150\times s\\\\s = 9 miles[/tex]