How Do I Convert Pounds to Kilograms?

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The discussion focuses on the distinction between weight and mass, highlighting that pounds measure force while kilograms measure mass. To convert pounds to kilograms, the formula is 1 pound equals approximately 0.45359237 kilograms, while 1 kilogram equals about 2.20462262 pounds. The conversation emphasizes the importance of understanding the role of gravity in these conversions, noting that weight in kilograms is often misunderstood. A simplified conversion factor of 2.2 is commonly used for quick estimates between pounds and kilograms. Overall, accurate conversions require consideration of gravitational acceleration, particularly in different environments.
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A pound being a measure of weight (force)and a kg being a measure of mass - how would I convert lbs. to Kg? If F=ma, Kg would be on the right of the equation and Lb. on the left which I don't think is equal since a lb. takes into consideration the acceleration of gravity and the Kg does not. I can't seem to put together the acceleration part. If I were to set an equation of - w=mg (w=weight)using the slug as the mass in this equation (similar to the m being the Kg in F=ma)would this be going in the right direction? Pounds v.s Kilograms?
 
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YOu are so correct in being bothered about how to convert pounds to kg. When we measure "weight" in kilograms, we are perpetuating a misconception.

What we mean is "the equivalent weight of this number of kilograms on the Earth's surface. Since most people will not go to a place where g is any different, it really doesn't matter on a daily basis.

To convert "kilograms to pounds" you are actually converting "the weight of so many kilograms" to pounds. THe shortcut: take the number of kilograms and multiply by 2.2. This product will be the weight (in pounds) of however many kilograms you have.
 
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Originally posted by Chi Meson
YOu are so correct in being bothered about this. When we measure "weight" in kilograms, we are perpetuating a misconception.
This is an issue that in practice, both systems screw up. A spring-scale measures weight, and a balance measures mass. In practice, neither differentiates between the two.
 
Thanks Chi.
What I am interested in is how do I get to the daily conversion of 2.2 Kg/Lb.? There has to be something or a formula to account for the acceleration of gravity. Can anyone come up with the actual conversion? I have been unable to find anything of the sort.
Hollywood
 
The weight in Newtons: (mass) x (g)

the conversion: one pound of force is exactly 4.448 Newtons.


take your kilograms, multiply by 9.801 m/s^2 (that's "g") then divide by 4.448 Newtons/pound, et voila.

Or, as I mentioned, keep the factor of 9.801/4.448 (that equals 2.203) to go directly from kilograms to pounds. (Remember, if you go to mars, you need to redo this)
 
Thanks Chi Menson!
That will help!

To convert from pounds to kilograms, you can use the following formula:

1 pound = 0.45359237 kilograms

To convert from kilograms to pounds, you can use the following formula:

1 kilogram = 2.20462262 pounds

To convert a specific number of pounds to kilograms, you can multiply the number of pounds by 0.45359237. For example, to convert 20 pounds to kilograms:

20 pounds x 0.45359237 = 9.0718474 kilograms

To convert a specific number of kilograms to pounds, you can multiply the number of kilograms by 2.20462262. For example, to convert 10 kilograms to pounds:

10 kilograms x 2.20462262 = 22.046226 pounds
 
Originally posted by Hollywood Dave
What I am interested in is how do I get to the daily conversion of 2.2 Kg/Lb.? There has to be something or a formula to account for the acceleration of gravity. Can anyone come up with the actual conversion? I have been unable to find anything of the sort.
Hollywood
That's 2.2 lb/kg. And the forumla is f=ma. Make two equations and set a=a. Good luck with the pounds to kg conversion.
 
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