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Comment by Waterluvian | Hacker News Reader

“The winch was rated to handle the moose’s weight—roughly 1,500 pounds”

Permit me on this wonderful Saturday morning to be tangentially pedantic.

I imagine the true “weight” of dragging a moose across the ground is a lot more than 1500lbs by probably many multiples?

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The weight the winch has to pull is the weight of the moose multiplied by the coefficient of static friction between the moose and road. This will be less than one so the weight the winch has to handle is less than the weight of the moose.

It’s been a while since high school physics, so I may be way off, but you only need to overcome the static friction of the object and surface.

It’s the reason I can push a large piece of furniture across a floor even though I could never lift it myself.

Valid for a spherical moose on a smooth plane with constant coefficient of friction, sure.

But an object dragged across a real surface will catch on things, and the force to overcome that is going to depend on the breaking strain of the objects and the elastic coefficients required to deform them.

That’s the reason that even a winch rated to the weight of your sofa can’t pull it through a doorway that’s too small for it.

> But an object dragged across a real surface

There are many different kinds of real surfaces.

A dead moose also has more give than a sofa.

I think you’re right and my intuition is way off.

Now I’m curious if the load is ever going to be greater than a dead lift, assuming no edge cases like being blocked behind a boulder. Ie. Just general ground friction and some incline plane angle less than 90deg.

That's determined by the coefficient of friction between the load and the surface. A coefficient of 1 means the force to drag is equal to the normal force (ie, the dead lift). Most things (including moose fur on soil) have a coefficient < 1, but it's not hard to engineer combinations > 1, such as race tires on asphalt.

I have been waiting for being able to use this link for some time now. Perhaps the results of dragging sheep are correlated: https://pubmed.ncbi.nlm.nih.gov/12507336/

Yes! The coefficient of friction can be greater than 1. For example, clean and dry rubber has a static coefficient of friction of 1.16, meaning that it takes 1.16x the force to move an object than the object exerts on the ground.

https://www.engineeringtoolbox.com/friction-coefficients-d_7...

(I think I’m correct here, but this is just from a quick google search and my very fuzzy recollection of high school physics)

For the inclined plane scenario, if you’re applying a force horizontally (eg by dragging with a rope) and the object has to slide up and over an inclined bump… even a frictionless incline of 45° will require you to pull horizontally with the more force than the object’s weight in order to get it to move.

Are you saying that he should've bought a lighter winch and a pair of wheels?

heavier winch about 2ton or he should have gut n cut it into quarters right there

But that would cover him in grass, perhaps. The quartering I mean.

the gutting should have been done early on but, put a garbage bag on or cover the moose in plastic, and stand to one side for the first part of the cut. its gotta be a quick opening or the inside will bloat out and make it a PITA to get it done without getting too messy.

I don't need to be able to lift 200 lbs to pull 200 lbs...

Yeah… I’m not actually sure what the right numbers would be.

I have to imagine that dragging 1500lbs across rough terrain and up out of a ditch might have a peak load greater than 1500lbs?

The guy nearly died man give him a break lmao

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