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trekkie1701c
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Stupid question here - what's the equation for determining the impact force of an object in freefall?
Stupid question here - what's the equation for determining the impact force of an object in freefall?
Alright. I dropped an approximately 40 pound rock from a 30 foot height onto a sheet of ice to determine whether the ice could widthstand enough force to hold my weight (trying to prove it without actually taking the risks associated with being wrong had I done it traditionally).
The only equations I've been able to find dealing with force pretty much boil down to getting the weight of an object, not force if an object has been falling for several seconds.
I'd say the best eqn to use would be F=dp/dt. Assuming that the rock comes to complete rest on impact, the force acting would be the mass of the rock times its velocity as it hits the ground (approximately).
40 pound rock from 30 feet! That should have bashed it good. Did the ice break? If not I bet it held you. If you slid a 40 pound rock onto the ice and listened for cracking, that would tell you more.
I'd say the best eqn to use would be F=dp/dt. Assuming that the rock comes to complete rest on impact, the force acting would be the mass of the rock times its velocity as it hits the ground (approximately).
My bad, i forgot to add about the impact time. Anyway I don't think this approach is practical for the case at hand. You should much rather try Luke's approach since the impact parameters are difficult to determine.I'd say the best eqn to use would be F=dp/dt. Assuming that the rock comes to complete rest on impact, the force acting would be the mass of the rock times its velocity as it hits the ground (approximately).