Question

1. a car accelerates from rest at 3 m/s² for 4 seconds. what is the final velocity? 3 m/s 12 m/s 1 m/s 4 m/s

Explanation:

Step1: Identify the formula

We use the formula $v = u+at$, where $v$ is final - velocity, $u$ is initial velocity, $a$ is acceleration and $t$ is time. Since the car starts from rest, $u = 0\ m/s$, $a = 3\ m/s^{2}$ and $t = 4\ s$.

Step2: Substitute the values

Substitute $u = 0$, $a = 3$ and $t = 4$ into the formula $v=u + at$. So $v=0+3\times4$.

Step3: Calculate the result

$v = 12\ m/s$.

Answer:

B. 12 m/s