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egrr10
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Homework Statement
The engineer of a passenger train traveling at 25.0 m/s sights a freight train whose caboose is 200 m ahead on the same track. The freight train is traveling at 15.0 m/s in the same direction as the passenger train. The engineer of the passenger train immediately applies the brakes, causing a constant acceleration of 0.100 m/s^2, while the freight train continues with constant speed. Take x=0 at the location of the front of the passenger train when the engineer applies the brakes.
If the speeds of the two trains and the deceleration of the passenger train remain as originally stated, how much of a head start would the freight train need in order to avoid collision?
Homework Equations
y=yo+vo*t+1/2*a*t^(2)
The Attempt at a Solution
I want to know if my set up is right.
I know then that yf(freight train) must be greater than yp(passenger) so knowing that they will collide at about 25 seconds, would I set
yf=yp and solve for distance?
yf=yo+vot
vp=vpot-(1/2)at^2
vo+(15m/s)=(25m/s)-(1/2)(-0.1m/s^2)