Respuesta :

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]