Weight is the force on the object due to gravity. DO NOT USE weight as a colloquial substitute for mass.
Weight is the force on the object due to gravity. Its SI-unit is Newton.
DO NOT USE the weight tag as a colloquial substitute for the mass tag.
Questions tagged [weight]
395 questions
121
votes
12 answers
Why don't we use weights to store energy?
One of the main reasons why we haven't switched to clean energy is the lack of efficient storage methods - But, why aren't we using dead weights to store energy and draw it back later when needed? As an example of what I mean:
Blake Angelo
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77
votes
5 answers
Do the weights of two liquids not add when mixed?
I was given an interesting dilemma today. A co-worker saw me adding a liquid (Diisopropyl ethylamine AKA DIPEA) to a flask filled with another liquid (Tetrahydrofuran AKA THF). I needed to weigh out exactly 5 grams of DIPEA into the THF and so I…
Brian
- 687
77
votes
20 answers
Is weight a scalar or a vector?
My professor insists that weight is a scalar. I sent him an email explaining why it's a vector, I even sent him a source from NASA clearly labeling weight as a vector. Every other source also identifies weight as a vector.
I said that weight is a…
Ryan
- 787
54
votes
3 answers
Will helium in the tires of a bike make it lighter?
I know that helium balloons float because it is less dense than air. I'm not expecting my bike to float, although that would be pretty cool. I just wanna know if replacing normal air with helium in the tires will produce a noticeable effect on its…
masterwarrior123
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51
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3 answers
What is the weight equation through general relativity?
The gravitational force on your body, called your weight, pushes you down onto the floor.
$$W=mg$$
So, what is the weight equation through general relativity?
user17093
51
votes
6 answers
Why do gases have weight?
I know that a gas is made of atoms or molecules moving freely in space.
When these particles hit the walls of where they're kept in they cause something called pressure.
But these particles never pile up on each other and push a surface down by…
Amir Moeini
- 647
28
votes
9 answers
Will a bathtub full of water weigh more if I add something that floats in the water?
Let's say I have a bucket or something bigger, like a bathtub full of water. I weigh that bath and get some value, $x$.
Then I add a small boat made of wood to that bathtub that doesn't touch the borders (i.e., it is only touching the water).
Will…
user1869935
- 1,209
25
votes
5 answers
What is the function of this complicated tensioning system?
I saw this arrangement for tensioning overhead cables from my train window (schematic below). Why not just have one pulley wheel leading directly to the weights? What function do the additional pulleys serve? For that matter, what are the cables…
mitte
- 396
25
votes
11 answers
What is the difference between weight and mass?
What is the difference between the weight of an object and the mass of an object?
Hobbs
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24
votes
4 answers
Which weighs more in atmosphere, $1\,{\rm kg}$ of steel or $1\,{\rm kg}$ of feathers?
I'm having a discussion at the moment regarding the mass of $1\,{\rm kg}$ of feathers and $1\,{\rm kg}$ of steel.
The person I'm arguing with states that $1\,{\rm kg}$ of feathers will be lighter when weighed, compared to the $1\,{\rm kg}$ of steel,…
James Thorpe
- 241
24
votes
13 answers
Would a gas "weigh" less than a liquid if they have the same mass?
Thought experiment: I acquired two boxes of the same dimensions and same weight. One box contains $1\ \mathrm{kg}$ of water at room temperature while the other box has $1\ \mathrm{kg}$ of water, but in steam form, because the temperature of the box…
Nova
- 1,288
23
votes
7 answers
Where on Earth does the mass of 1 kg actually produce a 1 kg reading on a digital scale?
Gravity on Earth varies by about 0.1% between poles and equator. If someone was buying/selling something mass critical e.g. gold, where is the standard place on Earth where a 1 kg mass produces a 1 kg reading as measured by a device like the…
user56903
22
votes
9 answers
Does the weight of an hourglass change when sands are falling inside?
An hourglass H weighs h. When it's placed on a scale with all the sand rested in the lower portion, the scale reads weight x where x = h.
Now, if you turn the hourglass upside down to let the sand start to flow down, what does the scale read?
I…
Gary Chou
- 333
22
votes
18 answers
Doesn't a box holding a vacuum weigh the same as a box full of air?
This was recently brought up, and I haven't been able to conclude a solid answer.
Let's say we have two identical boxes (A and B) on Earth, both capable of holding a vacuum and withstanding 1 atm outside acting upon them.
A is holding a vacuum,…
Chris
- 355
19
votes
4 answers
Why do we use kilograms instead of newtons to measure weight in everyday life?
What was the reason to use kilograms to measure weight (e.g. body weight, market vegetables etc.) instead of using newtons in everyday life?
Jake
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