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1. I noticed that our Calculations page say that in cases close to the ground and in cases far from the ground use different formulas. But what is "close to the ground", and how high is "far from the ground"?
2. The formula for "far from the ground" is "Ep = |(G*M*m)/r1 - (G*M*m)/r2|". r1 is the distance between the center of mass of the planet and the center of mass of the object before the fall / after being lifted (in meters). So usually it is radius of the planet (in case of earth 6371000 m) + how far the object is away from the ground before the fall / after being lifted. r2 is the distance between the center of mass of the planet and the center of mass of the object after the fall / before being lifted (in meters). So usually it is radius of the planet (in case of earth 6371000 m) + how far the object is away from the ground after the fall / before being lifted. Therefore, r1 > r2. Therefore, (G*M*m)/r2 > (G*M*m)/r1, which means the result I get is going to be negative. Am I misunderstanding something?
Note: Former calc group members, calc group members and Kaltias only
2. The formula for "far from the ground" is "Ep = |(G*M*m)/r1 - (G*M*m)/r2|". r1 is the distance between the center of mass of the planet and the center of mass of the object before the fall / after being lifted (in meters). So usually it is radius of the planet (in case of earth 6371000 m) + how far the object is away from the ground before the fall / after being lifted. r2 is the distance between the center of mass of the planet and the center of mass of the object after the fall / before being lifted (in meters). So usually it is radius of the planet (in case of earth 6371000 m) + how far the object is away from the ground after the fall / before being lifted. Therefore, r1 > r2. Therefore, (G*M*m)/r2 > (G*M*m)/r1, which means the result I get is going to be negative. Am I misunderstanding something?
Note: Former calc group members, calc group members and Kaltias only