Calculating acceleration with slug and lbs

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To calculate acceleration when a 30.0 lb force acts on a 12.2 slug mass, the formula a = F/m is used, where force is in pounds and mass is in slugs. The discussion clarifies that there is no need to convert units, as slugs are compatible with pound-force in this context. Participants suggest directly dividing the force by the mass, leading to an acceleration calculation. The correct approach results in an acceleration of approximately 2.46 ft/s², not the initially calculated 0.41 ft/s². Understanding the relationship between these units is essential for accurate physics calculations.
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Homework Statement



What is the acceleration when a 30.0 lb force acts on a 12.2 slug mass?

Homework Equations


a=F/m

The Attempt at a Solution



I can't quite figure out the slug thing. I took 12.2 slugs to be 392.5 lb/ft/s2
Then divided 30 by 392.5 lbs got canceled out and I'm left with ft/s2 in denominator which the is reversed because we are dividing fractions ? Is this right? I get 7.6 x 10 -2 ft/s2
Thanks a million!
 
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According to Wikipedia, 1 slug = 1 lbf/ft/s2.
 
hi tratata! :smile:
tratata said:
What is the acceleration when a 30.0 lb force acts on a 12.2 slug mass?

I can't quite figure out the slug thing. I took 12.2 slugs to be 392.5 lb/ft/s2
Then divided 30 by 392.5 lbs got canceled out and I'm left with ft/s2 in denominator which the is reversed because we are dividing fractions ? Is this right? I get 7.6 x 10 -2 ft/s2
Thanks a million!

no, you don't need to convert …

the whole point of using slugs is to keep things simple …

F = ma works fine if the mass is in slugs and the force is in lb-force :wink:

from the pf library on slug
In Europe, a slug is one of many varieties of gastropod mollusc.

In English-speaking countries, it is a unit of mass, equal to g pounds-mass (i.e., 32.17405 lbm). It is the amount of mass that will accelerate at one foot per second squared when one pound-force is applied.

It can be thought of as a pound-weight divided by 1 ft/s².

It is mostly used when "pound" is used to mean a force, and avoids the need of an extra constant in Newton's second law \mathbf{F}\ =\ m\mathbf{a}.

It is a unit in the gravitational foot-pound-second (fps) system.​
 
Hi tiny-tim! Thanks for your response! If a=F/m and I don't need to convert then I divide 12.2 by 30 I get 0.41 - where lbs gets canceled out and I'm left with ft/s2? Does that seem right? Thanks!
 
hi tratata! :smile:

(just got up :zzz:)
tratata said:
What is the acceleration when a 30.0 lb force acts on a 12.2 slug mass?
tratata said:
If a=F/m and I don't need to convert then I divide 12.2 by 30 I get 0.41 - where lbs gets canceled out and I'm left with ft/s2? Does that seem right? Thanks!

wouldn't it be better to divide the force by the mass? :wink:
 
It sure would )))))))
 
hello

hey guys i want to become a scientist and i need lessons
 
That's what school is for.
 
addaemark said:
hey guys i want to become a scientist and i need lessons

I've been using the internet for quite some time. I haven't become old enough for my first high school physics/chemistry class but that doesn't mean the the information isn't out there. Wikipedia is your friend.

Also this is a good site: https://www.khanacademy.org/science/physics

And this guy on youtube: https://www.youtube.com/user/DrPhysicsA
 
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