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## Main Question or Discussion Point

Today I was thinking how would I calculate the amount of force I would experience if I were to jump out of a second floor building in the event of a fire and if I had to jump how much force would be applied to me? I was able to find the height of the building by dropping an object from rest out of the window and found that the object hit the ground 1.63 seconds after dropping it.

This allowed me to use the equation

d=vi*t+.5at^2 and I was able to calculate the height of the building to be 13.03 m which seems reasonable.

I then went to calculate force and I only have the formula F=m*a which I know my mass is around 67 kg and my acceleration would be gravity. But this force is 657.27 N which is the same as the force of me standing on the ground.

I then decided to try and calculate the work done on me by the ground and my kinetic energy which then produced values of 8564 Joules and 8576 joules respectively. However this does not tell me the force at which I would hit the ground. It only tells me the energy I would apply to the ground supposing I remain inert when hitting the ground and conversely the energy that would be applied to me when I hit the ground.

I just want to know how much force I would hit the ground with and I cant seem to figure out how much force that would be. I know I would hit the ground with a final velocity of ~16 m/s and I know the acceleration is due to gravity and I know the time I would fall is 1.63 seconds but I cant find a way to calculate the amount of newtons that would be applied to me. And I know my acceleration is not going to change when I fall. But I also know from my lived experience that when I hit the ground falling from 13 meters I am going to be in much more pain than when I hit the ground falling from say 1 meter.

In short how can i calculate the amount of force I would hit the ground with because it seems I can find the velocity I hit the ground with, the amount of energy I would apply to the ground and thus the amount of energy the ground would apply back on me but I cant find the force that I would smack the ground with.

Thank you in advance!

This allowed me to use the equation

d=vi*t+.5at^2 and I was able to calculate the height of the building to be 13.03 m which seems reasonable.

I then went to calculate force and I only have the formula F=m*a which I know my mass is around 67 kg and my acceleration would be gravity. But this force is 657.27 N which is the same as the force of me standing on the ground.

I then decided to try and calculate the work done on me by the ground and my kinetic energy which then produced values of 8564 Joules and 8576 joules respectively. However this does not tell me the force at which I would hit the ground. It only tells me the energy I would apply to the ground supposing I remain inert when hitting the ground and conversely the energy that would be applied to me when I hit the ground.

I just want to know how much force I would hit the ground with and I cant seem to figure out how much force that would be. I know I would hit the ground with a final velocity of ~16 m/s and I know the acceleration is due to gravity and I know the time I would fall is 1.63 seconds but I cant find a way to calculate the amount of newtons that would be applied to me. And I know my acceleration is not going to change when I fall. But I also know from my lived experience that when I hit the ground falling from 13 meters I am going to be in much more pain than when I hit the ground falling from say 1 meter.

In short how can i calculate the amount of force I would hit the ground with because it seems I can find the velocity I hit the ground with, the amount of energy I would apply to the ground and thus the amount of energy the ground would apply back on me but I cant find the force that I would smack the ground with.

Thank you in advance!