PHYSICS: You're driving at 70 km/h when you accelerate with constant acceleration to pass another car.?

Question

You're driving at 70 km/h when you accelerate with constant acceleration to pass another car. Six seconds later, you're doing 75 km/h. How far did you go in this time?

Please show all steps and equations for the solution. Thank you.

Answer 1

There are four variables which put together in an equation can describe this motion. These are Initial Velocity (u); Final Velocity (v), Acceleration (a), Distance Traveled (s) and Time elapsed (t).

s = ut + 1/2 at2

u = 70km/h

t = 6 seconds or 1/600 h

a = (75km/h - 70km/h)/ t = (5km/h)/t

s = 70 km/h * (1/600 h)  + (1/2) ((5km/h)/t) * t^2

  = (70/600) + (1/2) (5) (1/600)   <--- note: one of the t has canceled out

  = .12 km or 120.8 meters.