Final answer:
The car's acceleration is calculated by converting the initial and final velocities from km/h to m/s and then applying the acceleration formula a = (vf - vi) / t, which gives an acceleration of 1.39 m/s².
Step-by-step explanation:
To calculate the car's acceleration, we need to first convert the speeds from km/h to m/s. The initial speed is 30 km/h, which is equal to 30 * (1000/3600) m/s or approximately 8.33 m/s. The final speed is 45 km/h, which is equal to 45 * (1000/3600) m/s or approximately 12.5 m/s. The time taken for this change in speed is 3 seconds.
Acceleration is defined as the rate of change of velocity with time. So, to find acceleration, we use the formula:
a = (vf - vi) / t
Where:
- vf is the final velocity,
- vi is the initial velocity, and
- t is the time interval.
Substituting the known values, we have:
a = (12.5 m/s - 8.33 m/s) / 3 s
a = 4.17 m/s / 3 s
a = 1.39 m/s²
Therefore, the car's acceleration is 1.39 meters per second squared (m/s²).