Answer:
-10 m/s²
Step-by-step explanation:
Certainly, let's make the calculation a bit simpler. To calculate the average acceleration, you can use the following formula:
Average Acceleration = (Change in Velocity) / (Time)
Given that the speed decreases from 100 km/h to 80 km/h in 5 seconds, the change in velocity is:
Change in Velocity = 80 km/h - 100 km/h = -20 km/h
Now, convert both initial and final velocities to m/s:
1 km/h = 1000 m/3600 s = 5/18 m/s
Initial Velocity = 100 km/h * (5/18 m/s per km/h) = 250/9 m/s
Final Velocity = 80 km/h * (5/18 m/s per km/h) = 200/9 m/s
Change in velocity in m/s:
Change in Velocity = (200/9 m/s) - (250/9 m/s) = -50/9 m/s
Average acceleration:
Average Acceleration = (Change in Velocity) / (Time) = (-50/9 m/s) / 5 s = -10/9 m/s²