Kinetic energy - Twice as fast equals four times the displacement!

Time stamps:
1:14 : dropping 100g from 19,5cm
1:44 : dropping 100g from 78cm
2:21 : discussing the results
6:37 : double checking the displacement heights
10:18 : proving that it went twice as fast

[@disparslab326]

Time stamps:
1:14 : dropping 100g from 19,5cm
1:44 : dropping 100g from 78cm
2:21 : discussing the results
6:37 : double checking the displacement heights
10:18 : proving that it went twice as fast

[@_John_Sean_Walker]

The one on the left bounced back up a little bit.
When you want to measure the depth, you can lay a straight piece of wood or something like a ruler on top of the foam, and then measure the depth.

[@disparslab326]

Yes seems like an obvious thing to use 😂. I just did some tests with a heavier weight (so hopefully it wont bounce upwards again) and i let it drop from 9 times higher (3 times as fast) and it produced around 9 times the displacement! Will make a video soon proving the quadratic relationship of kinetic energy

[@_John_Sean_Walker]

@@disparslab326 Yes, quadratic: mgh = ½mv² because: v = √(2hg) of course.

[@disparslab326]

@@_John_Sean_Walker Hi John, here is an update (little bit disappointing): I noticed that now the block of foam bounced a little when i dropped the mass from 1 height, therefore some energy was lost. So i placed some weights on the block to hold it still. The mass then produced a little bit more displacement.
Here are my results:
Dropped from 1 height (11cm): 0.9cm displacement
Dropped from 4 height (44cm): 2.9cm displacement
Dropped from 9 height (99cm): 5.2cm displacement
2.9/0.9 = 3.2 (instead of 4 theoretically)
5.2/0.9 = 5.7 (instead of 9 theoretically)
As you see, the results are in between the predictions of kinetic energy and momentum (if momentum is energy).
I will try out clay now

[@_John_Sean_Walker]

@@disparslab326 I don't know the shape of the probes, but the ones in the video had a pretty flat shape, so more cylindrical shapes would do better.

[@disparslab326]

This was the probe:
discountoffice.be/p/schietlood-op-blok-1-kg/
​@@_John_Sean_Walker

[@stephenbrough8132]

I wonder if you could just fill it with flour, scrape off the excess and weight it - all a bit unnecessary really since we can already see the results are close enough considering small errors. Nice job Dispar.

[@stephenbrough8132]

PS bang goes his desperate claim that spherical masses were giving the wrong result.

[@disparslab326]

Thank you Stephen,
since it is cylindrical, the only information we need is the height. The diameter always remains the same, in contrast with a sphere. So no need to fill it up and measure the volume. As you can tell, twice the velocity gave us roughly 4 times the height. When calculating the volume with the formula, that will give us also the same result. Filling it up and measuring the weight will also be the same then. No?

[@stephenbrough8132]

@@disparslab326 I just thought it might be a little more accurate measure of the same thing than reading a mm scale ruler by eye with possibly very slight (fractions of a mm) differences in depth (around the circumference) that are hard to determine. it's not a deal reaker for me, Dispar - I perfectly accept the accuracy is good enough for disproving Gary's claims. I was only thinking every bit of extra accuracy is useful to know, so we can be as sure as humanly possible whether this is a better method than clay or anything else. I'm not picking holes in your work mate - I'm only making suggestions in case you or anyone else might feel they are worthwhile. I guess you would need scales like Michael's that can measure mg - Can;t remember whether yours already do and can't check right now as I'm screen recording something. I agree it's unlkely to be worth the extra effort anyhow and there may be extra problems with my idea anyhow, such as ensuring that whatever you filled it with wasn't accidentally more compressed in one example than another - flour could be vulnerable to that. When I used liquid to measure the displacement, that had it's own problems too - the surface tension causing a slightly raised surface for instance. I bet even if we used some high tech laser method or whatever, it wouldn;t make the slightest difference to Gary anyway. Look forward to any more experiments you do.