Question

1. a car accelerates uniformly from rest at 3.2 m/s². when the car has traveled a distance of 40. meters, its speed will be a) 8.0 m/s b) 12.5 m/s c) 16 m/s d) 128 m/s

Explanation:

Step1: Identify the relevant kinematic - equation

The kinematic equation $v^{2}=v_{0}^{2}+2ad$ is used, where $v$ is the final velocity, $v_{0}$ is the initial velocity, $a$ is the acceleration, and $d$ is the displacement.

Step2: Substitute the given values

Given $v_{0} = 0\ m/s$ (starts from rest), $a = 3.2\ m/s^{2}$, and $d = 40\ m$. Substituting into the equation: $v^{2}=0^{2}+2\times3.2\times40$.

Step3: Calculate the value of $v^{2}$

$v^{2}=2\times3.2\times40=256$.

Step4: Solve for $v$

Taking the square - root of both sides, $v=\sqrt{256}=16\ m/s$.

Answer:

C. 16 m/s