To determine the time needed for the car to reach 20 m/s, we can use the equation of motion:
v = u + at
Where: v = final velocity (20 m/s) u = initial velocity (10 m/s) a = acceleration (2 m/s²) t = time
Rearranging the equation, we have:
t = (v - u) / a
Substituting the given values:
t = (20 m/s - 10 m/s) / 2 m/s² t = 10 m/s / 2 m/s² t = 5 s
Therefore, the time needed for the car to reach 20 m/s is 5 seconds.