Need Help with a Physics Problem - Calculating Height of Falling Particle

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A user seeks assistance with a physics problem involving a falling particle that covers 64% of its total height in the last second of its fall. They express difficulty in applying the correct equations and request guidance. Another participant encourages sharing the attempted equations for better assistance and clarifies the concept of instantaneous velocity, explaining it in terms of calculus and tangent lines. The original poster later confirms they found a solution with some help. The discussion highlights the importance of understanding both the physics of falling objects and the mathematical principles involved.
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Hi, I'm having a bit of trouble with a problem..

basically the question is as follows:
A particle falling covers 64% of the entire height in its last second of the fall. What is the total height of the fall?

I've tried equating two formulas, and a few other things but I can't seem to go anywhere. Any help would be appreciated.

I also need clarification on something.. My teacher said that on a position-time graph, that if there is a portion that has constant velocity (ie, no curve but a straight line), that you can't have instantaneous velocity since you can't draw a tangent to a point.. but I was under the impression that instantaneous velocity was just the velocity and any given point of time?

Thanks!
 
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Hi Skyblitz,

Post your equations which you tried, so we can see if/where there is a problem.

EDIT: Re the instantaneous velocity, you can have one. The subject which covers it is (dum, dum, dum, da!) calculus. Basically, you get the instantaneous velocity by taking two close points, and bringing them closer and closer together, watching what the intersecting line does. As the distance between the points approaches zero, the intersecting line becomes the tangent.
 
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As enigma said, show us what equations you have equated or other things you have done and we will guide you.
 
Thanks for your help!
Sorry I didn't post the equations as I fell asleep yesterday night after studying [zz)]

But I did, with some help, figure out how to do it.
 
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