You are driving down the highway late one night at 20 m/s when a deer steps onto the road 35 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 10 m/s2 . How much distance is between you and the deer when you come to a stop?
A.
Sort the variables for the period from t2=0.5s until the car comes to rest, at time t3, based on whether their values are known or unknown.
FROM : a(x) , x (initial), time, v (initial) , x (final), v (final)
B.
Sort the variables for the period from t2=0.5s until the car comes to rest, at time t3, based on whether their values are known or unknown.
FROM : a(x) , x (initial), time, v (initial) , x (final), v (final)
A.
Sort the variables for the period from t2=0.5s until the car comes to rest, at time t3, based on whether their values are known or unknown.
FROM : a(x) , x (initial), time, v (initial) , x (final), v (final)
B.
Sort the variables for the period from t2=0.5s until the car comes to rest, at time t3, based on whether their values are known or unknown.
FROM : a(x) , x (initial), time, v (initial) , x (final), v (final)
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In the first 0.50 s, the car moves 0.50*50 = 10 m
The distance traveled with initial velocity V0 and acceleration a to the stopping point is s = V0²/(2*a) = 20 m
total distance car moves = 30 m; distance from the deer = 35 - 30 = 5 m
The distance traveled with initial velocity V0 and acceleration a to the stopping point is s = V0²/(2*a) = 20 m
total distance car moves = 30 m; distance from the deer = 35 - 30 = 5 m