Question

A car slows down at -5.00 m/s2 until it comes to a stop after traveling 15.0 m. How much time did it take to stop.

Answer 1

Answer:

2.45 seconds to the nearest hundredth.

Step-by-step explanation:

Acceleration a = -5, distance s = 15, time  = ?.

Final  velocity = v =  0.

We need to use the equations of motion under constant acceleration.

v^2 = u^2 + 2as       where u is the initial velocity

0 = u^2 + 2*-5*15

u^2 = 150

so u = √150

Now we use v = u + at:

0 = √150 - 5t

t = √150/5

t = 2.45 seconds.