Factual error: In the movie, when the elevator ("the fall") reaches the middle of the planet, everything turns weightless. In reality, everything should have turned weightless as soon as the elevator was dropped, given they're in freefall.
Factual error: The movement of "the fall" as depicted in the movie is utterly impossible. The distance between the Colony and the Federation is about 6 000 miles, and the trip takes 17 minutes. This means that the fall would have to travel at an average speed of 20 000 miles per hour, or faster than the space shuttle in earth orbit! Given that it accelerates at the start and decelerates at the end the maximum speed would be even higher, and the acceleration required would be considerably more than 1G. Not only does the fall move at much slower speeds in all the scenes showing its movement but this speed would only be possible in a vacuum, which is not the case since people actually move outside the fall while it is moving.
Factual error: If you drive a straight shaft through the earth's core from London (52deg N, 0deg E) down to the other side of the world it would come out at 52deg South, and 180 East. Which is somewhere out in the South Pacific ocean over 500km from New Zealand's South Island, not on mainland Australia.
Suggested correction: The fall transport thing would actually make the passengers feel zero G force as they will be falling at the same rate and when falling objects accelerate. Another fact is that when an object gets closer to the core of a planet it will have a greater acceleration due to the law of gravity. The equation is (gravitational acceleration) = (gravitational constant) multiplied by (mass of planet) divided by (distance from centre of mass or core as it's called) squared. The earth's core is liquid due to the density of the iron which is the result of the massive acceleration due to gravity at that distance from the core. If a person were to fall from one side of earth to the other it would only take 42 minutes to travel the 12,800km.
That would still be an average speed over the whole journey of 18,286 Km/h (11,785 mph). Slower at the ends, faster during the middle section.
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