Final answer:
The acceleration of a car that goes from 0 to 100 km/hr in 10 seconds is 10 km/hr/s. To find this, convert the speed to m/s, calculate the acceleration in m/s², and then convert it back to km/hr/s.
Step-by-step explanation:
To calculate the acceleration of a car that goes from rest to 100 km/hr in 10 seconds, we use the formula for acceleration (a), which is the change in velocity (Δv) divided by the change in time (Δt). The initial velocity is 0 km/hr, and the final velocity is 100 km/hr. The time taken for this change in velocity is 10 seconds.
First, convert the final velocity to meters per second (m/s) since acceleration is traditionally measured in m/s². Since 1 km/hr is approximately equal to 0.27778 m/s, the final velocity in m/s is 100 km/hr × 0.27778 m/s per km/hr = 27.778 m/s.
Now, calculate the acceleration using the formula:
a = Δv / Δt = (27.778 m/s - 0 m/s) / 10 s = 2.778 m/s²
To express this acceleration in km/hr/s, we reverse the conversion factor:
2.778 m/s² × (3.6 km/hr per m/s) = 10 km/hr/s
Therefore, the car's acceleration is 10 km/hr/s.