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• Draft
• When Scott picked the objects up on the Moon, they would have felt, or â€˜weighedâ€™ much lighter than if he picked them up on Earth.
• This is because weight comes from gravity, and it changes depending on where you are.
• changes depending on where you are. If you weigh 100kg on Earth but jump onto a set of scales on the Moon, theyâ€™ll register less than 17kg. This is because weight is actually a measure of how strongly gravity is pulling you down.
• Mass just recalibrates things to find out what theyâ€™d weigh if they were under Earthâ€™s gravitational force. On the Earth, thereâ€™s no need to calibrate anything, and mass and weight are equal. This is why in casual usage the words are interchangable, but in physics they are not.
• It converts the weight of an object to what it would have weighed on Earth, so your mass on the Moon is also 100kg. It does this because it's defined as a measure of resistance to acceleration.
• From <https://ideas.discover.earth/mass/>
• For instance, gold atoms are more massive than iron atoms, which are more massive than hydrogen atoms.
• Gold atoms definitely have more protons and neutrons in them than the iron atoms in the hammer, and the mix of atoms in its wooden handle.
• But this isn't quite where mass comes from.
• The large mass of objects like the Earth and the Sun is
• If someone went into the source code of the universe and switched off mass, then your next footstep would propel you into space. A few moments later you'd realise that the sun has been extinguished, the atmosphere is floating away, and the Earth is hurtling into the darkness of space.
• You'd pretty much ruin the universe.
• But such a fundamental aspect of the universe originates way, way down in the tiniest of places. Within the atom.
• Mass arises from not just your atoms, or even from the protons and neutrons within them. It comes from the world inside protons and neutrons, called quantum mechanics.
• According to the Standard Model, a proton consists of two up 'quarks' and one down 'quark', and a neutron has the opposite. Each one also has a great many number of 'gluons' holding them together (technically, they cause the strong nuclear force that holds the quarks together). Gluons = the glue that holds everything together.
• It's not even about gold having more protons and neutrons in its atoms than the hammer does, because //quarks// are massless particles.