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A comment on Gravity is not a force – free-fall parabolas are straight lines in spacetime. Parent comment

Re:Gravity is not a force – free-fall parabolas are straight... by the_arun on Monday October 19, 2020 @04:01AM (#24824188)
Something I learnt in 8th grade - if an object is free falling from sky of mass "m" the force it applies when it hits on the ground is m * g, where g is the gravitation.
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Re:Gravity is not a force – free-fall parabolas are straight... by nsonha on Monday October 19, 2020 @07:55AM (#24825488)
I think you are mashing up different lessons:

- when you stand on the ground you are the subject of 2 forces: gravitational force m * g and the opposite reaction force of the ground surface, they cancel each other so you stand still

- when you free fall your acceleration is g and the gravitational force is m * g, this is according to Newton's 2nd law

when you hit the ground depending on your velocity and... deformation, the force of impact will be different because you will de-accelerate to 0 or even bounce back very quickly much faster than g. It's gonna be much stronger than g * m

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