the physics of chopping

[squishware]

I need to interrupt this thread to say I love xkcd. Thank you that is all, good night (Brekenridge)

 

[LittleBill]

It is entirely possible to model the impact of a knife hitting a piece of wood in a way that provides useful and real world applicable information.

That would be very helpful.

I began this thread by pointing out that the kinetic energy with which blade hits wood is proportional to the square of the velocity; thus a small increase in velocity can make up for a large difference in blade weight...

obviously, there are real world limits to this: as someone pointed out, one can only increase swing velocity by so much...

but I'm no physicist, and it would be great to hear the lowdown from someone who is... when and if you have the time and the inclination...

and yeah, the scorn which some posters are heaping on science is amusing; considering that they're using computers to post their opinions...

 

[Ultimate]

This thread saddens me a lot. I've avoided reading most of what has been said recently because it reminds me too much of some of the clueless students I've had to deal with


The biggest problem with high school / intro college level physics? Many professors don't put enough effort into exaplaining just how simple the stuff they are teaching is, and how much MORE sophisticated understanding exists of even simple things like kinematics. What you end up with is a bunch of students who know just enough to convince themselves that they understand things well, and then they start making all kinds of crazy statements, like the ones we are seeing in this thread.

It is entirely possibly to model the impact of a knife hitting a piece of wood in a way that provides useful and real world applicable information. Most of what has been discussed in this thread is in no way connected to that possibility

While I am only a college level student, I don't see how anything I've said can qualify as a "crazy statement". I'm pretty sure I addressed the main issue that was asked by the first poster. If I was wrong about anything, I'd very much like to know.

P.S. If you're referring to what I said about it being useless to analyze the chopping motion, I think you've misunderstood me. I simply meant that it was not necessary to analyze the entire process and include every last variable because something as simple as kinetic energy can be used to show how velocity influences said energy more than mass. And that was what the initial question was anyway. Again, If I'm wrong about this I would very much like to be corrected.

 

[MustardMan]

I'd be interested in the modeling too, but unless you can convince the NSF to give me grant money to approach the problem, I am not going to put the needed effort into it

 

[rbmcmjr]

I need to interrupt this thread to say I love xkcd.

Me too. The overwhelming majority of the people in my division at work have Physics degrees (even though the job title is Radiological Engineer), but one of us has a math degree. He embodies the geekiness shown in this strip.

Thank you that is all, good night (Brekenridge)

Are you in Breckenridge? My folks told me it was snowing like a bugger there today.