Final answer:
The acceleration of the racecar is calculated using the formula a = Δv / Δt, which results in an acceleration of -8.22 m/s². This negative acceleration indicates the car is slowing down.
Step-by-step explanation:
To calculate the acceleration of a racecar whose velocity decreases from 73.0 m/s to 36 m/s over a 4.5 second period, we can use the formula for acceleration, which is the change in velocity (Δv) divided by the time interval (Δt):
Acceleration (a) = Δv / Δt
Here, Δv is the final velocity (vf) minus the initial velocity (vi), and Δt is the time over which the change occurs. Plugging in the values:
Δv = vf - vi = 36 m/s - 73 m/s = -37 m/s
Δt = 4.5 s
Therefore, the acceleration is:
a = Δv / Δt = -37 m/s / 4.5 s = -8.22 m/s²
The negative sign indicates that the racecar is decelerating, or slowing down.