Rennata Gas is driving through town at 25.0 m/s and begins to accelerate at a constant rate of -1.0 m/s2. Eventually Rennata comes to a complete stop.
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Vf^2=Vi^2+2ad where Vf=0, Vi=25m/s, a = -1m/s^2, d is distance. Plug in the numbers
0 = 25^2 +2*(-1)*d => d = 25^2/2 = 312.5m
Or
Vf = Vi + a*t => 0 = 25 -1*t => t=25s =>
d = Vi*t+(1/2)*a*t^2 = 25*25 -0.5(25)^2 = 625 - 625/2 = 312.5m
0 = 25^2 +2*(-1)*d => d = 25^2/2 = 312.5m
Or
Vf = Vi + a*t => 0 = 25 -1*t => t=25s =>
d = Vi*t+(1/2)*a*t^2 = 25*25 -0.5(25)^2 = 625 - 625/2 = 312.5m