why we are expressing weight(force) in mass units(Kg)?

Question

[ weight is a force ,the unit of force is newton.But we are expressing in Kg(unit of mass)]

Answer 1

typically, I would imagine that earth-gravitational acceleration is tacitly assumed

there is a difference between "conversational" speech (demotic) and "technical" speech

Answer 2

When we talk about a mass of 20 Kg, it means the contents in the matter is 20 Kg in mass units. It will never change. But the weight has to be expressed in newton as it relates to the gravitational force. But, in practice we express the term weight to mean mass of the item which in real sense not correct.

Answer 3

It is a defect of terminology originating in the fact that we often equate mass and weight. I actually posted a question some time ago because I was confused. How could 1 liter of water have a mass of 1kg AND WEIGH 1kg, when the weight is supposed to be m*g, where g= accel of gravity? The answer is: because that's what we call it. If I put a liter of water on the scale, it will apply a force on the scale of 1kg * 9.8 m/sec^2 or 9.8 newton. However, if I look at the scale reading, it says 1kg! So when the scale says 1kg it means 9.8 newton. Technically the term for the weight reading on the scale is kgwt (kilogramweight), not kg. and we are erroneously abbreviating the correct term.

Answer 4

This is a misunderstanding which shows the difference b\w common people and scientists

Common people refer to mass as the weight of the body

while scientists refer the force acting on the body as it's weight.

The usage depends on the context and the person using it

Answer 5

this is because you can use an objects weight and its mass to figure out how it is behaving. Gravity on the earths surface is 9.87 kg/s^2. This tells you how an object will accelerate, depending on its weight and mass.
weight is measured in kg bc it is useful in determining answers for formulas. It can be represented both ways

Answer 6

It's sloppy but common practice. A scale should properly be calibrated in newtons, since it measures the earth's gravitational force on an object, but usually one wants to know the actual mass, and since the earth's gravity is nearly equal everywhere on the surface, it is convenient to calibrate the scale in kilograms.

Answer 7

force = mass X acceleration

since weight is the same as force towards center of earth, g is assumed.