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Need quick help with finding positional equation

  • #1

Homework Statement


A huge tractor and a Tesla full of school children come driving along a winding
mountain road, in opposite directions. The tractor has a speed of
40.0km/h and the car zooms along with 80.0km/h. The Tesla suddenly comes around a
corner, sees the tractor, and they both immediately start braking, both with
constant accelerations of 5.00m/s^2 (opposite to their directions of motion).
a) If the initial distance between the two is 60.0m, do they hit each other? If
so, where, and with what relative speed on impact? If not, what is the distance
between the two when they both stop?

Homework Equations


x(t)= -a/2*t2 + v*t + x

Dont know how to find the positional equations of the two vehicles and then solve for t to find where they crash.
 

Answers and Replies

  • #2
FactChecker
Science Advisor
Gold Member
5,391
1,957
Pick one of the vehicles as your frame of reference (so its position is always at x=0) and use the combined relative velocities, accelerations, etc. in your equation to calculate the other vehicle's position. See how far that gets you.
 
Last edited:

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