To find the acceleration of the race car, we can use the formula for acceleration:
\[ a = \frac{\Delta v}{\Delta t} \]
where:
- \( \Delta v \) is the change in velocity,
- \( \Delta t \) is the change in time.
In this case, the initial velocity (\( v_i \)) is 20 m/s, the final velocity (\( v_f \)) is 60 m/s, and the time (\( \Delta t \)) is 5 seconds.
First, we calculate the change in velocity:
\[ \Delta v = v_f - v_i = 60 , \text{m/s} - 20 , \text{m/s} = 40 , \text{m/s} \]
Now, we can plug this value into the acceleration formula:
\[ a = \frac{40 , \text{m/s}}{5 , \text{s}} = 8 , \text{m/s}^2 \]
Therefore, the car's acceleration is 8 m/s².