Question

A car starting from rest accelerates at a rate of 8.0 m/s/s. What is its final speed at the end of 4.0 seconds?

Answer 1

To calculate the final speed of the car at the end of 4.0 seconds, you can use the following kinematic equation:

$v=u+at$

Where:

• $v$ is the final velocity (the speed we want to find).
• $u$ is the initial velocity (which is 0 m/s for a car starting from rest).
• $a$ is the acceleration of the car (given as $8.0{\text{m/s}}^2$).
• $t$ is the time it takes to reach the final velocity (given as $4.0\text{s}$).

Substitute the given values into the equation and solve for $v$:

$v=0\text{m/s}+(8.0{\text{m/s}}^2)\times 4.0\text{s}$

$v=0\text{m/s}+32.0\text{m/s}$

$v=32.0\text{m/s}$

The final speed of the car at the end of 4.0 seconds is $32.0\text{m/s}$ or $32.0\text{meters per second}$.