The relative speed is 16.63m/s, and the relative deacceleration is 2.1m/s^2
47=16.63t+1/2 2.1 t^2
putting it in standard form..
1.1t^2+16.63t-47=0
t= (-16.63+-sqrt(277+207)/2.2
I don't get your time for the first.
Relative speed can be found knowing the correct time by..
v=initialrelatlivespeed*time-1/2 2.1 t^2
A bullet train is traveling at 23.3 m/s when it approaches a slower train 47 meters ahead traveling in the same direction at 6.67 m/s.
If the faster train begins decelerating at 2.1m/s^2 while the slower train continues at constant speed, how soon will they collide?
I got 3.68 seconds.Using the quadriatic formula.
If the faster train begins decelerating at 2.1m/s^2 while the slower train continues at constant speed, at what relative speed will they collide?
I got 8.5 m/s from subtracting 15.2 (what I got from the quadriatic formula)from 6.67 (slower train).
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