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Homework Statement
A truck starts from rest and accelerates at 0.9m/s2. 0.8s later, a car accelerates from rest at the same starting point with an acceleration of 2.5m/s2
Where and when does the car catch the truck?
Homework Equations
Motion equations
Xf-Xo=Vox(t)+1/2(a)(t)^2
The Attempt at a Solution
x truck=x car
1/2(a)(t)^2=1/2(a)(t-0.8s)^2
1/2(a)(t)^2=1/2(a)(t^2-1.6t+0.64)
1/2(0.9)t^2=1/2(2.5)(t^2-1.6t+0.64)
0.45t^2=1.25t^2-2t+0.8
0.8t^2-2t+0.8t=0
quadratic equation =
2+1.2/1.6=2s
2-1.2/1.6=0.5s
I don't know where I went wrong but the value for time isn't working for me. The assignment continues to say the answer is incorrect... Please help me pin point my error so I can correct myself.
Thank you
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