If a car accelerates at a uniform 4.0 m/s2, how long will it take to reach a speed of 80 km/hr, starting from rest? .

5.6s

Explanation:

Step1: Identify the given parameters

acceleration(a) = 4m/s²

initial velocity (u)= 0 (since the car started from rest)

final velocity (v) = 80km/hr

final velocity(v) in m/s =

=

=22.22m/s

Step2: calculate the time it takes the car to attain speed of 80km/hr = 22.22m/s

acceleration(a) = change in velocity per time

a= 5.555 seconds

a≅5.6s

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