Part A You\'re driving down the highway late one night at 20 m/s when a deer ste

Question

Part A You're driving down the highway late one night at 20 m/s when a deer steps onto the road 56 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? Express your answer to two significant figures and include the appropriate units 36 Pnevtoun Answers Reauest Anewer Submit X Incorrect: Try Again: 2 attempts remaining Part B What is the maximum speed you could have and still not hit the deer? Express your answer to two significant figures and include the appropriate units. U- 1 Value Units

Explanation / Answer

Vi = 20 m/s
Vf = 0.0 m/s
d = 56 m
T = 0.50 s
a = -10 m/s^2

We know that,
D = Vi * T
D = (20 m/s) * (0.50 s)
D = 10 m

Now, how far you went after you hit the brakes.

Dd = [ Vf^2 - Vi^2 ] / [ 2 * (-10 m/s^2) ]
Dd = [ (0.0 m/s)^2 - (20 m/s)^2 ] / (-20 m/s^2)
Dd = [ -400 m^2/s^2 ] / (-20 m/s^2)
Dd = 20 m

Total distance traveled
Dt = D + Dd
Dt = (10 m) + (20 m)
Dt = 30 m

Ds = d - Dt
Ds = (56 m) - (30 m)
Ds = 26 m
So you come to a stop 26 meters before hitting him.

Maximum Speed
v^2 = u^2 - 2ad
0 = u^2 - 2*10*30
=> u = sqrt(2*10*30)
= 24.5 m/s

I hope help you.....

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