Science:Math Exam Resources/Courses/MATH102/December 2011/Question 08 (ii)
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Question 08 (ii) 

You are driving down the highway when you see a sleeping moose. You apply the brakes and carefully stop your car 20m away from the animal. While you are looking for your camera the moose wakes up. It instantly charges toward your car at a constant speed of 8m/s. One second later, you start backing away from the moose at a constant acceleration of 2m/s^{2}. (ii) At what time T does the moose hit your car? 
Make sure you understand the problem fully: What is the question asking you to do? Are there specific conditions or constraints that you should take note of? How will you know if your answer is correct from your work only? Can you rephrase the question in your own words in a way that makes sense to you? 
If you are stuck, check the hint below. Consider it for a while. Does it give you a new idea on how to approach the problem? If so, try it! 
Hint 

Use your answer from part i) to answer this question. Also consider: what is the distance between the car and the moose when the moose and the car collide? 
Checking a solution serves two purposes: helping you if, after having used the hint, you still are stuck on the problem; or if you have solved the problem and would like to check your work.

Solution 

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Please rate my easiness! It's quick and helps everyone guide their studies. From our answer in part i), the distance between the moose and the car is given by d(t), where To solve for the time when the moose hits the car we solve the equation d(T) = 0 to get T. Since the moose will not hit the car twice, we choose the smaller of the two times, and say the moose will hit the car at 