Question

1. a car approaches a stop sign going 5 m/s before it comes to a stop. if it does this in 4 seconds, what was its acceleration?

Explanation:

Step1: Identify the known - values

Initial velocity $u = 5\ m/s$, final velocity $v=0\ m/s$, time $t = 4\ s$.

Step2: Use the acceleration formula

The formula for acceleration is $a=\frac{v - u}{t}$.
Substitute the values: $a=\frac{0 - 5}{4}$.

Step3: Calculate the acceleration

$a=\frac{- 5}{4}=-1.25\ m/s^{2}$.

Answer:

$-1.25\ m/s^{2}$