Jumping to Travel

Question:

if a person standing in one place on the earth was able to jump vertically and hold that vertical jump for an extended period of time remaining motionless, would the earth rotate beneath cause that person to land at another location on the earth when he fell back to earth. what law does this represent?

Answer:

You suggest that a person jump vertically and somehow "hold that vertical jump for an extended period of time remaining motionless". Assuming for the moment that holding the vertical jump is possible, the "remaining motionless" issue has some problems.

First of all the idea of "motionless" implies an absolute reference point with which to compare our position so as to know when we are motionless. Mr. Einstein's theories suggest that there exists no such reference point. Let's get past that difficulty by fixing a position relative to distance stars an saying that for the purposes of this experiment we will consider that point to be "motionless".

Imagine that we are going to conduct your experiment on the equator where the effect of the Earth's rotation is maximum. The circumference of the Earth is about 25,000 miles and a person standing "still" on the Earth surface at the equator completes that distance in 24 hours so the persons speed is over 1000 miles per hour without even counting the motion of the Earth around the Sun or the motion of the Sun around the center of the galaxy or the motion of the galaxy around who knows what.

Our jumper then can not "remain motionless" since she or he is not motionless at the start of the experiment. It is possible for certain military aircraft to jump approximately vertically and travel for a while to the west at a speed which will exactly cancel the speed of the Earth's rotation at the equator. To "remain motionless" in this case requires tens of thousands of horsepower. This is because the Earth's atmosphere travels along with the Earth's surface, creating about a 1000 plus mile per hour wind for "motionless" objects.

I hope this discussion helps. There are some fairly sophisticated issues I have not covered, around this interesting question. If you need more information let me know.

JDJones