To calculate the acceleration, we need to convert the initial and final velocities to the same unit (km/h) and divide the change in velocity by the time taken.
Given: Initial velocity = 18 km/h Final velocity = 72 km/h Time = 30 seconds
Converting the velocities to km/h: Initial velocity = 18 km/h Final velocity = 72 km/h
Change in velocity = Final velocity - Initial velocity Change in velocity = 72 km/h - 18 km/h Change in velocity = 54 km/h
Acceleration = Change in velocity / Time Acceleration = 54 km/h / 30 seconds
Simplifying the units: Acceleration = (54 km/h) / (30/3600) h Acceleration = (54 km/h) / (0.008333 h) Acceleration = 6480 km/h² / h
Therefore, the acceleration of the car is 6480 km/h².