1. The problem statement, all variables and given/known data An escalator is 20.0m long. If a person stands on the escalator, it takes 50.0s to ride from bottom to the top. a) if a person walks up the moving escalator with a speed of 0.500 m/s relative to the escalator how long does it take for the person to get to the top. 2. Relevant equations V = d / t 3. The attempt at a solution I'm not understanding relative motion too well. I begin by calculating the velocity of the escalator which is 0.400 m/s. Since the person is walking up with a speed of 0.500 m/s in relation to the escalator, does that mean that if the escalator was not there, he'd be walking at 0.500 m/s? Why would I not add the two velocities (.4 + .5) and isolate for the time?