physics
posted by olga .
If your car accelerates from rest at a steady rate of 4 m/s2, how soon will it reach 81 km/h (50.3 mph or 22.5 m/s)?

physics 
Nadir
Current velocity = (time)*(acceleration) + initial velocity
22.5 = time*4 + 0
time = 22.5/4 = 5.625 seconds
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