Two trains, one traveling at 60 miles/hr and the other at 80 miles/hr, are headed toward one another on a straight level track. When they are 2.0 miles apart, both engineers simultaneously see the other's train and apply their brakes. If the brakes decelerate each train at the rate of 3.0 ft/sec^2, determine whether there is a collision.(adsbygoogle = window.adsbygoogle || []).push({});

Ok, so is it correct to say that if [itex] d > \frac{(v_{1}-v_{2})^{2}}{2a} [/itex] there will be no collision, and if [itex] d < \frac{(v_{1}-v_{2})^{2}}{2a} [/itex] there will be a collision (d is distance, v is velocity, and a is acceleration). When I do this, I get that there will be a collision, but the correct answer is that there will be no collision. What am I doing wrong?

Thanks

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# Determine whether there is a train collision

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