Grace is driving her Ford at 75.0 km/h, when she sees a stop sign, 45.0 m ahead, she slows down the car at a rate of 4.50m/s^2. Would Grace be able to stop the car at the stop sign? Explain

Answer 1

75 km/h = 75000 m/h = 75000 m / 3600 s = (75000/3600) m/s = (750/36) m/s

Stopping distance is s

where v^2 = u^2 + 2as

v = final speed = 0 m/s

u = initial speed = (750/36) m/s

a = acceleration = -4.50 m/s/s

Sub these into the equation and solve for s.

If s < 45 then she can stop the car at the stop sign