How many steps high is the escalator in question? About how tall is each step? What is the greatest possible error? Least step height? Greatest step height? In ft?
What is our measured V? Least V? Greatest V? What is the greatest possible error?
How long is each step? What is the greatest possible error? Least length? Greatest length? In ft?
What is our measured H? What is our least H? Greatest H? What is the greatest possible error?
How do we find P? Least V = Least H = Measured V = Measured H = Greatest V = Greatest H = Least P = Measured P =Greatest P =
What else do we need besides distance? Video of Escalator Trip
How long is one trip? What is the greatest possible error in that measurement? What unit do we need for time? In minutes, what is our least time? Greatest time?
We can now use DIRT to help us find our speed. Recall that d = rt (distance is rate x time) What is our least speed? What is our greatest speed? What is our measured speed? Which speed gives us the greatest possible error? What is our percent error? So what does r = ?