Monday, February 8, 2016

http://www.dailymail.co.uk/sciencetech/article-3014408/It-takes-38-minutes-fall-centre-Earth-Journey-four-minutes-fas...

Originally shared by Jim Slater

http://www.dailymail.co.uk/sciencetech/article-3014408/It-takes-38-minutes-fall-centre-Earth-Journey-four-minutes-faster-previously-thought-density-taken-account.html

Assuming the earth is a solid sphere of equal density (which it isn't - but for simplicity's sake), I calculated that it would take 38 minutes, 1 second. The most common answer is 42 minutes, 12 seconds.

In the article below, Alexander Klotz at McGill University in Montreal came up with a calculation of 38 minutes, 11 seconds, strangely close to my simple calculation.

Maximum velocity would be reached at the half-way point; the remainder of the fall would be spent decelerating until you reached a velocity of 0 (zero) just as you arrived at the other end of the hole.

Interestingly enough, the estimated velocity after falling half way through the earth is almost exactly the same as the escape velocity of 25,020 mph (40,270 km/h) - the velocity required to break free of earth's gravitational field.

I wonder why this is so?
http://www.dailymail.co.uk/sciencetech/article-3014408/It-takes-38-minutes-fall-centre-Earth-Journey-four-minutes-faster-previously-thought-density-taken-account.html

No comments:

Post a Comment