High School Difference between "1 kgf" and "1 N"?

[navneet9431]

What is the difference between 1 kgf and 1 Newton?

 

[Merlin3189]

About 10. Actually standard g, which is more like 9.8
Since f=ma
g N = 1 kg x g m/sec²
1 kg force = 1 kg x g m/sec²

Both are units of force. N is the SI unit. kg force is a non-SI unit.

 

[sophiecentaur]

1 kgf

Before getting carried away with this, where have you ever found the term "kgf" used in serious Physics? The whole point is that, in SI, Force and Mass do not share any officially named units.
When I was taught Imperial units at school, we used Poundals as the basic unit of force and lbs as Mass. If we talked about a pound force, it was frowned upon. More than fifty years later, users of Imperial units are still falling into the same sort of pitfalls. Every day, people persist with using the same sort of units that were invented when steam engines and horses and carts were the norm. Time for a serious attempt at moving to a system that was developed in a better informed era, I think. It was done successfully in UK in my lifetime (via cgs and mks) so US could easily manage it.

 

[Dale]

What is the difference between 1 kgf and 1 Newton?

I am with @sophiecentaur on this. I have been doing this stuff for decades and never seen kgf until today. I don’t know if any system of units actually officially recognizes it

 

[olivermsun]

There may be confusion because one does see the units $\mathrm{lb}\cdot\mathrm{f}$ (for reasons that may be worth discussing).

 

[navneet9431]

There may be confusion because one does see the units $\mathrm{lb}\cdot\mathrm{f}$ (for reasons that may be worth discussing).

My doubts are still unclear.
Is there no difference between "1 kilogram force" and "1 Newton"?

 

[russ_watters]

My doubts are still unclear.
Is there no difference between "1 kilogram force" and "1 Newton"?

This was answered in post #2: the difference is 9.8kgf/N.

 

[sophiecentaur]

My doubts are still unclear.
Is there no difference between "1 kilogram force" and "1 Newton"?

How can there be a "kilogram force"? The Force of a kilogram, doing what?
The 'old' system with pounds and feet was 'invented' when the weight of an object was thought to be more relevant than its mass. We know different nowadays.

This was answered in post #2: the difference is 9.8kgf/N.

I don't think so. Where does a force come from unless the conditions are properly specified? If you really feel it necessary, the term kgW (kilogram weight) would at least have some meaning, but even that is very sloppy.

 

[russ_watters]

How can there be a "kilogram force"? The Force of a kilogram, doing what?
...
I don't think so. Where does a force come from unless the conditions are properly specified? If you really feel it necessary, the term kgW...

https://en.m.wikipedia.org/wiki/Kilogram-force

 

[sophiecentaur]

https://en.m.wikipedia.org/wiki/Kilogram-force

That reference tells us that " The kilogram Force is a non standard unit and is unacceptable for use in SI"
Does that resolve the issue? I know Wiki is not the fount of all knowledge.

 

[russ_watters]

That reference tells us that " The kilogram Force is a non standard unit and is unacceptable for use in SI"
Does that resolve the issue?

Yes, I think it does. it's like slang; it may not be in a normal dictionary, but people still use it and it has a definition.

 

[navneet9431]

1 kg force = 1 kg x g m/sec2

What is "g" there?Is it for grams?
I have read that 1 Newton(N)= 1 kg*m/s^2

 

[Dale]

What is "g" there?Is it for grams?

No. In that context g is the standard acceleration due to gravity at the surface of the earth. So 1 g = 9.80665 m/s^2

 

[russ_watters]

What is "g" there?Is it for grams?
I have read that 1 Newton(N)= 1 kg*m/s^2

No, "g" is the standard acceleration due to gravity at the surface of the earth.

 

[sophiecentaur]

Yes, I think it does. it's like slang; it may not be in a normal dictionary, but people still use it and it has a definition.

I bet you wouldn’t appreciate my entering a list of other terms that fit that description and expect them to be taken seriously, though. PF normally aims at the straight and narrow path.

 

[russ_watters]

I bet you wouldn’t appreciate my entering a list of other terms that fit that description and expect them to be taken seriously, though. PF normally aims at the straight and narrow path.

Please drop it. The OP asked a specific question and I gave an accurate answer. It doesn't even conflict with yours, so there is really nothing to argue about!

 

[CWatters]

I have read that 1 Newton(N)= 1 kg*m/s^2

In general..

Force(N) = mass(kg) * acceleration(m/s^2)

So yes..

1N = 1kg * 1m/s^2 = 1kgm/s

However as others have said, the expression kgf isn't used in SI units. I would encourage you to forget you ever heard about kgf and make sure you can understand how to work with Newtons.

Examples...

A 1kg mass sitting on a table on Earth exerts a force of 9.8N on the table.
A 100N force accelerates a 5kg mass at 20m/s^2

 

[sophiecentaur]

Please drop it. The OP asked a specific question and I gave an accurate answer. It doesn't even conflict with yours, so there is really nothing to argue about!

No argument. I'm just concerned that the OP and others shouldn't make free use of 'inappropriate' quantities or units.

 

[olivermsun]

I don't see a problem. A poster asked a question about an unfamiliar unit that he/she may have encountered somewhere. Whether or not one likes the units, they are out there, and an explanation can be given for what the units mean along with reasons to avoid them.

 

[CWatters]

Just for info, the OP also has a thread open asking why k=1 in Newton's F=kma. I'm using the app so hard to post a link to that thread.

Edit: actually I figured out how to do that..

https://www.physicsforums.com/index.php?threads/944707/