Acar starts from rest at a stop sign. it accelerates at 2.0 m/s2 for 5.0 seconds, coasts for 3.0 s , and then slows down at a rate of 1.5m/s2 for the next stop sign. part a how far apart are the stop signs?

88.3m

Explanation:

In this problem there are three sections

you must state the equations as appropriate

attached solution

88.33 m

Explanation:

For AB:

u = 0, t = 5 s, a = 2 m/s^2

Let the distance between A and B be s1 and the velocity at B is v.

Use second equation of motion

s1 = 25 m

Use first equation of motion

v = u + a t

v = 0 + 2 x 5 = 10 m/s

For BC:

Let the distance from B to C is s2.

time = 3 s,

speed, v = 10 m/s

s2 = v x t = 10 x 3 = 30 m

For CD:

final velocity, v' = 0

initial velocity, v = 10 m/s

acceleration, a = - 1.5 m/s^2

Let the distance from C to D is s3.

Use third equation of motion

s3 = 33.33 m

The total distance covered is s

s = s1 + s2 + s3 = 25 + 30 + 33.33 = 88.33 m

i think it’s a. this is because if they measured the mass of something with a mass of 150g, then their final answer would have to be approximately 150g. though all of their answers are almost 150, rosa and tran have the closest answers (or the exact answer) to the accurate one.

i think the answer is a and b

i wish you luck