To determine the acceleration of the car in meters per second squared (m/s²), we need to convert the speed from kilometers per hour (km/h) to meters per second (m/s) and then divide it by the time taken.
First, let's convert the speed from km/h to m/s. We know that 1 km/h is equal to 1000 meters per hour (m/h), and 1 hour is equal to 3600 seconds (s). Therefore, we can use the following conversion:
90 km/h * (1000 m/1 km) * (1 h/3600 s) = 25 m/s
Now, we can calculate the acceleration:
acceleration = change in velocity / time
The change in velocity is given by the final velocity minus the initial velocity. Here, the initial velocity is 0 m/s (as the car starts from rest), and the final velocity is 25 m/s (as calculated above).
change in velocity = 25 m/s - 0 m/s = 25 m/s
The time taken is given as 10 seconds.
acceleration = (25 m/s - 0 m/s) / 10 s = 2.5 m/s²
Therefore, the acceleration of the car is 2.5 m/s².