The problem involves a scenario where an engineer must determine the minimum deceleration required to stop a locomotive before reaching a car stuck on the tracks. The context includes initial speed, distance to the crossing, and the engineer's reaction time.
The discussion is ongoing, with participants exploring different methods to approach the problem. Some have provided partial calculations and suggested alternative equations, while others are clarifying the assumptions and parameters involved in the scenario.
Participants are working under the constraints of the problem as posed, including the specified initial conditions and the requirement to avoid an accident. There is uncertainty regarding the correct application of kinematic equations and the interpretation of time variables.
First, use the formula d=vt to find the distance he travels before applying the brakes. Subtract that distance from 210 m. Then, use the formula:runner1738 said:An engineer in a locomotive sees a car stuck on the track at a railroad crossing in front of the train. When the engineer first sees the car, the locomotive is 210 m from the crossing and its speed is 10 m/s. If the engineer's reaction time is .22 s, what should be the magnitude of the minmum deceleration to avoid an accident? Answer in units of m/s^2
You got the first part (the 207.8m) right. As for the rest, you canot use 22s and the time, since you don't know the time it will take hime to stop. (Sorry, I gave you the wrong formula).runner1738 said:210-2.2=d=207.8=10(22)+1/2(a)(22)^2 ? ? or is 21.78 for time?
runner1738 said:210-2.2=d=207.8=10(22)+1/2(a)(22)^2 ? ? or is 21.78 for time?