Do two braking cars collide if 45m apart?

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Homework Statement


Car 1 travels 50km/hr
Car 2 travels 100km/hr
The Cars are 45m apart
Car 1 slams on brakes and stops in 8m


a) Calculate deceleration of Car 1? (Car 1 has the same deceleration as Car 2)

b) Use deceleration to find the distance it took Car2 to stop?

c) Did the cars hit?



The attempt at a solution
Car 1 = 50 km/hr = 13.89 m/s
Car 2 = 100 km/hr = 27.78 m/s


a) Vf^2-Vi^2 = 2a(Delta x)
0 - 13.89^2 = 2a(8)
-192.932=16a
a= -12.05 m/s^2

b) 0-27.78^2=2(-12.05)x
-771.7=-24.1x
Distance it took Car2 to stop is = 32 m

c) 45-32= 13m apart



IS THIS RIGHT?
 
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