Answer to Question #285523 in Physics for princeomega

Question

a railroad engine moves forward along a straight section of track for a distance of 15 m due west at a constant speed of 3.4m/s. It then immediately stops, reverses its direction and travel east at a constant speed of 4.3m/s.

a) What is the time required for the entire process?

Answer 1

The time required for the entire trip consists in the time to cover all three paths:

$$t_1=d/v_1=15/3.4=4.4\text s.\\ t_2=d/v_2=15/4.3=3.5\text s.\\ t=t_1+t_2=7.9\text s.$$