A biker traveling the road is 100 km away from his destination, at t=0 (initial time). His speed, at the start point, is 100km/hour, and varies equalys to his distance from the final destination, decreasing. So, after 40 km traveled(and therefore 60 km away from his target) he is at 60 km/h. H

How much time will it take until he reaches his destination? What is the function that express the position of the biker?

I think this might help: http://hyperphysics.phy-astr.gsu.edu/hbase/avari.html

EDIT: That is NOT a homework assignment. I created this question in my head.

So, i worked a little, and find the following equations:

V = -s + 100

Since ds/dt = velocity , => ds/dt = (-s+100) ds/(-s+100) = dt

ln 100 - ln (100 - s)

So, how i find the equation of acceleration? thats the real question.


closed as off-topic by David Z Mar 23 '16 at 15:37

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  • $\begingroup$ HINT:- make an equation and then find derivative! $\endgroup$ – user5954246 Mar 23 '16 at 15:43
  • 2
    $\begingroup$ Please take a minute and read the meta site. The homework tag is not just for homework questions, but for exercises similar to homework that require basic calculations and no physical concepts. $\endgroup$ – Martin Mar 23 '16 at 18:23