What is the relationship between kg wt and Newtons through dimensional analysis?

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SUMMARY

The relationship between kilogram weight (kg wt) and Newtons (N) is defined by the equation 1 kg wt = 9.81 N, where kg wt represents the force required to accelerate a mass of 1 kg at 9.81 m/s² due to gravity. Dimensional analysis confirms that kg wt is a unit of force, equivalent to 9.81 N. This relationship is established through the formula W = ma, where W is weight, m is mass, and a is acceleration due to gravity. The kilogram-force is an arbitrary unit, similar to the pound-force, which is defined as 1 lb = 4.448 N.

PREREQUISITES
  • Understanding of Newton's second law of motion (W = ma)
  • Familiarity with units of force, specifically Newtons and kilogram-force
  • Basic knowledge of dimensional analysis
  • Concept of gravitational acceleration (approximately 9.81 m/s² on Earth)
NEXT STEPS
  • Study the concept of dimensional analysis in physics
  • Learn about the differences between mass and weight in physics
  • Explore the implications of gravitational acceleration on force calculations
  • Investigate other units of force and their conversions, such as pounds to Newtons
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Students of physics, educators teaching mechanics, and professionals in engineering or physical sciences who need to understand the relationship between mass, weight, and force.

sphyics
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i know its a unit for force... I'm intrigued by the relation 1kgwt=9.8N?

by dimensional analysis

L.H.s [M2L1T-2 {since wt=kgm/s2}
R.H.S [M1L1T-2
i understand I'm wrong somewhere, but I'm not able to figure it out, so pls help me :)

Also how to get the relation between both.( think 9.8 is the contribution of 'g')
 
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sphyics said:
i know its a unit for force... I'm intrigued by the relation 1kgwt=9.8N?

by dimensional analysis

L.H.s [M2L1T-2 {since wt=kgm/s2}

You interpreted kg wt as mass*weight. A kilogram weight is a unit of force. Specifically, it is the force needed to make a mass of 1 kg accelerate by 9.80665 m/s2.
 
D H said:
You interpreted kg wt as mass*weight. A kilogram weight is a unit of force. Specifically, it is the force needed to make a mass of 1 kg accelerate by 9.80665 m/s2.
yes

and how to get the relation 1kgwt=9.8N mathematically.
 
You can't derive it. The kilogram-force (sometimes called the kilogram-wt) is defined as the force needed to make a one kilogram of mass accelerate by 9.80665 m/s2.
 
sphyics said:
how to get the relation 1kgwt=9.8N mathematically.

1 kgwt means the "weight of a mass of 1 kg on earth". So:

W = ma = (1 kg)(9.81 m/s²) = 9.81 N = 1 kgwt

kgwt is an arbitrary defined unit for force, just like 1 lb = 4.448 N
 
jack action said:
1 kgwt means the "weight of a mass of 1 kg on earth". So:

W = ma = (1 kg)(9.81 m/s²) = 9.81 N = 1 kgwt

kgwt is an arbitrary defined unit for force, just like 1 lb = 4.448 N

Thanks for ur explanation now i understand
 

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