Question

You're driving down the highway late one night at 16 m/s when a deer steps onto the road 39 m in front of you. Your reaction time before stepping on the brakes is 0.50 s, and the maximum deceleration of your car is 12 m/s^2 . How much distance is between you and the deer when you come to a stop? What is the maximum speed you could have and still not hit the deer?

Answer 1

Speed = 16 m/s

Distance = 39 m

Reaction time = 0.50s

Max. deceleration = 12 m/s ^2

Solution:

1. Distance = Speed × Time

39m = 16 m/s × 0.50s

39m = 8 m/s

Distance = 39m / 8 m/s = 4.875 m/s

When it comes to a stop :

Max. deceleration – distance

= 12 m/s ^2 – 9.75m = 2.25m ^2

D = 2.25 m ^2

2. Max. Speed = D / Time

= 2.25 m/s ^2 ÷ 16 m/s

= 0.140625 m/s ^2

( I am not sure of the answer so pls check the units and calculations )