Four travel on different sections of a long straight track. taking north to be positive direction, rank the trains in order by velocity, from most negative to most positive. the trains move as follows: train A moves north with a speed of 10 m/s. train B heads south and has twice the speed of train A. train C also heads south and has twice the speed of train A. train D travels north and covers 24m in 2 s. what is the answer?

You are driving to the grocery store at 20 m/s. you are 110m from an intersection when the traffic light turns red. assume that your reaction time is 0.50s and that your car brakes with constant acceleration. how far are you from the intersection when you begin to apply the brakes? what acceleration will bring you to rest right at the intersection? how long does it take you to stop after the light changes? the known values: vi=20m/s xi=110m t=.50s vf=0m/s xf=0m a=?