(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

at the instant the traffic light turns green, s starts from rest and accels at a_s. at the same time k passes s with constant velocity v_k.

given a_s, v_k,

find distance before the cross again

time it takes to do so

velocity of s at this point

plot the position as a function of time for both. take x=0 at the intersection <- no idea what last sentence means.

2. Relevant equations

v_s = a_s + t

d = 1/2 a_s * t^2

v_s^2 = 2a_s*d

d= v_k * t

3. The attempt at a solution

t = sqrt(2*v_k/a_s)

d = v_k * sqrt(2d/a_s)

v_s = a_s*sqrt(2d/a_s)

as for this plotting, does this mean I "start" the graph at their intersection? which one?

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# Homework Help: 1d motion question

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