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this is a physics question that requires a lot of math. Hoping on of you genius could help me.

Q: You're driving down the highway late one night at 16m/s when a deer steps onto the road 44m in front of you. Your reaction time before stepping on the brakes is 0.50s , and the maximum deceleration of your car is 10m/s2 .

How much distance is between you and the deer. I solved this =23m

What is the maximum speed you could have and still not hit the deer?

The answer is 25 m/s. A lot of people had stated to use the quadratic formula. I just don't know where to begin.

Respuesta :

W0lf93
I don't know why you need the quadratic formula.  

If it takes 0.5 seconds before stepping on the breaks while going 16 m/s, then you travel 8 meters before anything happens. That means you are 44-8 = 36 meters away from the deer now. 
 v^2 = v_initial^2 + 2(acceleration)(distance)
 0 = (16 m/s)^2 + 2(-10m/s^2)(distance)
 256 m^2/s^2 / (2(10 m/s^2) = distance = 12.8 meters (13 meters after significant figures are taken into account). 
 The maximum speed would be: 
 0 = v_initial^2 + 2(-10m/s^2)(36m)
 v_initial^2 = 720m^2/s^2
 v_initial = 27 mph

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