What does the weighing scale we use in our homes actually measures? As weight should be in Newton and it measures in Kilograms so does it measures our mass ? Why we say that our weight is x Kilograms when we should say the weight is x Newtons , it is too confusing for me .

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Mass has no unit and it represents the amount of material in something.

Weight of an object is the force acting on it due to gravity and is defined as mass * force of gravity. And on earth we use lbs, kg, stone, etc. But you could also use newtons.

Newtons is a force where 1 newton is the force required to accelerate 1 kg by 1 m/s/s.

On Earth, there is little difference between saying your weight vs your mass, because the force of gravity is pretty well constant across the surface. So while the scale is directly measuring weight, it’s as trivial as dividing by 9.8 to give you mass in kilograms.

It senses your weight, it is then calibrated to report your mass in kg.

If you were to stand on it at the equator vs one of the poles your weight would be slightly different, so it’s reported mass would be different.

If you were to take it to the moon and stand on it it would sense your weight on the moon, and report a very wrong answer for your mass due to calibration being completely off.

To directly measure mass you’d need to be stuck in a centrifuge or hooked up to some giant springs or similar to accelerate you back and forth. This is cumbersome and not in common use, hopefully for obvious reasons.

For the folks using 🦅🦅🇺🇸🇺🇸FREEDOM UNITS🇺🇸🇺🇸🦅🦅 your scales also measure your weight in pounds-force, and are then calibrated to report your mass in pounds-mass, and you’ll see the same deviations from your actual mass at the poles and on the surface of the moon as the metric folks.

While the ‘seconds’ hand of your clock actually measures the time as it passes, the minute and hour hand merely divide the number by 60 each and show it to you.

Similarly the weight is measured as a force, divided by ~9.8 and shown to you as ‘mass’.

Only a balance scale with a counter weight can actually measure mass.

When we measure weight in X kilograms, what we *mean* is a force of X kilograms times the force of Earth’s gravity. 1 kilogram weight is 9.8 kg m/s^2 in force, i.e., 9.8 Newton. This is the force exerted by gravity on an object with a mass of 1 kg.

Since humans mostly live on the surface of the Earth, where the force of gravity is very close to constant, we can measure mass by measuring weight for most purposes.