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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While kilogram is a measure of mass and newton is a measure of force, on earth, in many non-scientific settings we default to swapping around some units to have the same intent. Kilograms is mass, so while the scale is detecting force it displays them in terms of the force (weight) of a body (on earth) of this many kilograms.
If you have to travel to another planet or moon or something you could probably ask the scale company to make one appropriate for that location.
While kilogram is a measure of mass and newton is a measure of force, on earth, in many non-scientific settings we default to swapping around some units to have the same intent. Kilograms is mass, so while the scale is detecting force it displays them in terms of the force (weight) of a body (on earth) of this many kilograms.
If you have to travel to another planet or moon or something you could probably ask the scale company to make one appropriate for that location.
Wel its actually quite simple.
We dont because we like to differentiate things.
A newton is used to see how much force an amount of stuff would take to move more specifically 1 newton is the amount of force needed to move 1 kilogram of stuff 1m/s. So the calculation for weight is part of the calculation for newtons but not the whole calculation
For reference the calculation for weight is m(mass) * g(standard acceleration / gravity where 9.8 is used)
And the calculation for force or newtons usually is that calculation(mg) * m(a number of meters) /s(second) ^2
Because technically if you hold something its not actually exerting any force on your body. It is not moving or being moved. It simply changed positions to in your hand or on your scale so you now feel the gravity that has always been pulling on it due to the mass it has.
Its all just a matter of specification.
And as per your question of does kilograms measure mass. If you look at the calculations again you see mass is a part of how we get kilograms, so no its not directly referring to your mass but if you divide you weight by 9.8 you would get very close to what your mass is. (the 9.8 is an average and not accurate it changes based on your distance from sea level)
Assuming you stay on the same planet, weight and mass are directly proportional. (Almost) anywhere on Earth, 1 kg is 9.8 N. So essentially the scale is measuring force in Newtons, but just displaying that weight in kilograms (or more accurately, “kilogram-forces”).
If you took your scale to the moon and tried to weigh yourself there, it would be wrong because it’s not calibrated to make that conversion.
Wel its actually quite simple.
We dont because we like to differentiate things.
A newton is used to see how much force an amount of stuff would take to move more specifically 1 newton is the amount of force needed to move 1 kilogram of stuff 1m/s. So the calculation for weight is part of the calculation for newtons but not the whole calculation
For reference the calculation for weight is m(mass) * g(standard acceleration / gravity where 9.8 is used)
And the calculation for force or newtons usually is that calculation(mg) * m(a number of meters) /s(second) ^2
Because technically if you hold something its not actually exerting any force on your body. It is not moving or being moved. It simply changed positions to in your hand or on your scale so you now feel the gravity that has always been pulling on it due to the mass it has.
Its all just a matter of specification.
And as per your question of does kilograms measure mass. If you look at the calculations again you see mass is a part of how we get kilograms, so no its not directly referring to your mass but if you divide you weight by 9.8 you would get very close to what your mass is. (the 9.8 is an average and not accurate it changes based on your distance from sea level)
Bathroom scales measure resistance. The springs can push back up to a certain amount of force, and the dial (or potentiometer in an electronic scale) is connected to the spring in such a way that how much it turns points to what fraction of the max force was applied.
Say a scale is rated for 300 pounds. A person who’s 150 pounds steps on, the spring compresses halfway and then hits the point where it’s pushing upward with the same force as the plate is being pushed down- that’s equilibrium. The dial is calibrated so that halfway is marked “150 lbs,” but what it’s really telling you is how far down the person pushed the plate before the spring started pushing back.
You can have fancier scales with magnetometers instead of a mechanical linkage, but it’s still following the same logic:
* The plate is this far away
* The spring stops up to this much force
* The spring stopped this much of the max force to stop the plate here
* Therefore, this is the weight that was applied to the scale
Bathroom scales measure resistance. The springs can push back up to a certain amount of force, and the dial (or potentiometer in an electronic scale) is connected to the spring in such a way that how much it turns points to what fraction of the max force was applied.
Say a scale is rated for 300 pounds. A person who’s 150 pounds steps on, the spring compresses halfway and then hits the point where it’s pushing upward with the same force as the plate is being pushed down- that’s equilibrium. The dial is calibrated so that halfway is marked “150 lbs,” but what it’s really telling you is how far down the person pushed the plate before the spring started pushing back.
You can have fancier scales with magnetometers instead of a mechanical linkage, but it’s still following the same logic:
* The plate is this far away
* The spring stops up to this much force
* The spring stopped this much of the max force to stop the plate here
* Therefore, this is the weight that was applied to the scale
Assuming you stay on the same planet, weight and mass are directly proportional. (Almost) anywhere on Earth, 1 kg is 9.8 N. So essentially the scale is measuring force in Newtons, but just displaying that weight in kilograms (or more accurately, “kilogram-forces”).
If you took your scale to the moon and tried to weigh yourself there, it would be wrong because it’s not calibrated to make that conversion.
If you’re in an environment where gravity is constant, then weight and mass are basically interchangeable. There’s no real difference between saying an apple has a mass of 0.1kg as saying it weighs 1N when you’re standing still on earth.
The difference becomes apparent when you start to accelerate up or down, or go into orbit, or go do another planet or moon. But for the vast majority of human existence and scientific inquiry, we have been dealing with static objects on earth, so the distinction hasn’t been that important.
You could imagine a future where people have colonised Mars, Earth has been abandoned, and somebody asks on ELI5 why “The Moon” is the name of a moon orbiting a different planet from the one they are on. We are creatures of habit, and it takes effort to change names for things!
If you’re in an environment where gravity is constant, then weight and mass are basically interchangeable. There’s no real difference between saying an apple has a mass of 0.1kg as saying it weighs 1N when you’re standing still on earth.
The difference becomes apparent when you start to accelerate up or down, or go into orbit, or go do another planet or moon. But for the vast majority of human existence and scientific inquiry, we have been dealing with static objects on earth, so the distinction hasn’t been that important.
You could imagine a future where people have colonised Mars, Earth has been abandoned, and somebody asks on ELI5 why “The Moon” is the name of a moon orbiting a different planet from the one they are on. We are creatures of habit, and it takes effort to change names for things!
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