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dochummer
01-26-2007, 05:54 AM
Ok, so it's been a while. But I figure there are some people that may remember the appropriate equations. I was wondering, how much force is required to move a palet jack carrying a 1000lbs load? I know there are many variables that affect the answer...but just wondering if anyone could give a relatively simple answer. Thanks! :)

MarineHawk
01-26-2007, 11:09 AM
Ok, so it's been a while. But I figure there are some people that may remember the appropriate equations. I was wondering, how much force is required to move a palet jack carrying a 1000lbs load? I know there are many variables that affect the answer...but just wondering if anyone could give a relatively simple answer. Thanks! :)

Strictly speaking, any force will move it (laterally), no matter how small.

Force = mass times acceleration. Because the mass remains constant here, the greater the force, the greater the acceleration - the smaller the force, the smaller the acceleration, but even a miniscule force will move it.

There, done.

Wait, there's more.

Small forces will not in reality move the pallet jack significantly because there are numerous elements of friction that must be overcome to move a heavy pallet jack sitting on a planet with one G-force of gravity. In short, it depends on the amount of friction involved - mostly in the mechanical systems of the jack. For example, it should require more force to push a 2,000 lb cart with a stone axle like the Egyptians used 3,000 years ago to move their big rocks around than it would to push a 2,000 lb modern car - unless, of course, it's a Ford.

As far as the friction calculations, here's Wikepedia's explanation:


The classical approximation of the force of friction known as Coulomb friction (named after Charles-Augustin de Coulomb (http://en.wikipedia.org/wiki/Charles-Augustin_de_Coulomb)) is expressed as:
http://upload.wikimedia.org/math/e/8/e/e8e1f02fe2beae94c593488169463a23.png, where-
μ is the coefficient of friction (http://en.wikipedia.org/wiki/Coefficient_of_friction), N is the normal force (http://en.wikipedia.org/wiki/Normal_force) to the contact surface, Ff is the maximum possible force exerted by friction. This force is exerted in the direction opposite the object's motion, thus it is an opposing force.
This law mathematically follows from the fact that contacting surfaces have atomically close contacts only over extremely small fraction of their overall surface area, and this contact area (http://en.wikipedia.org/wiki/Contact_area) is proportional to load (until saturation (http://en.wikipedia.org/wiki/Saturation) which takes place when all area is in atomic contact thus no further increase of friction force takes place).
This simple (although incomplete) representation of friction is adequate for the analysis of many physical systems.


This is complicated further because static friction is generally greater than kinetic friction. That is why it generally requires more force to start accellerating something where there are opposing friction forces than it does to keep it moving.

h2co-pilot
01-26-2007, 07:49 PM
Where's Paragon?:jump: :D :jump:

KenP
01-26-2007, 08:07 PM
Read this:
http://www.roymech.co.uk/Useful_Tables/Tribology/co_of_frict.htm

Mr. I - Man
01-26-2007, 08:09 PM
Ok, so it's been a while. But I figure there are some people that may remember the appropriate equations. I was wondering, how much force is required to move a palet jack carrying a 1000lbs load? I know there are many variables that affect the answer...but just wondering if anyone could give a relatively simple answer. Thanks! :)

Simple answer have you ever pushed a car in neutral? Well a car weighs much more than a 1000 lbs pallet and its wheels are larger and not solid.

Just do it!!

Big Z
01-27-2007, 02:44 AM
Ok, so it's been a while. But I figure there are some people that may remember the appropriate equations. I was wondering, how much force is required to move a palet jack carrying a 1000lbs load? I know there are many variables that affect the answer...but just wondering if anyone could give a relatively simple answer. Thanks! :)


just wondering if anyone could give a relatively simple answer.


Hey! YOU! ......Move the Fkn Palet! ;)