4 ms·
On Earth.
by a9h74j 5y ago
On Earth.
- Hamcha 5y agoDepends how you measure it. Any X kg/lbs of matter here on earth is still that same X kg/lbs everywhere in the universe. Assuming the scale being used to weight is correctly calibrated to whatever planet it's in, it would still show up as the same amount of kg/lbs.
- a9h74j 5y agoDepends upon what you set out to measure. lbs is specifically a unit of force. kg is specifically a unit of mass. It is a category error to equate these as measures, although (in many places) an everyday convention to do so on Earth. IIRC the English unit for mass is the slug. If the tecnical limit is 70lbs or so, that is must technically be read as lbs force -- aka force of gravity which varies with location.
- rzzzt 5y agoKilopond or kilogram-force is the force with which a 1 kg object is pushing on its base: https://en.wikipedia.org/wiki/Kilogram-force https://en.wikipedia.org/wiki/Kilogram-force
- dragonwriter 5y ago> lbs is specifically a unit of force Incorrect. The avoirdupois pound (lb) is historically a unit reflecting the long conflation of mass and force, but the modern unit of that name is expressly a mass unit that is a derived unit of the kilogram. The corresponding unit for force is the pound-force, (lbf).
- zmgsabst 5y agoWikipedia lists it as a unit of mass — as defined by the amount that exerts a certain force. https://en.wikipedia.org/wiki/Pound_(mass) https://en.wikipedia.org/wiki/Pound_(mass) The pound unit of force is abbreviated ‘lbf’. https://en.wikipedia.org/wiki/Pound_(force) https://en.wikipedia.org/wiki/Pound_(force)
- jrochkind1 5y agoyou could really take USPS for a ride by shipping something to Venus!
- grog454 5y ago"a teaspoon of neutron star material would weigh around a billion tonnes." https://astronomy.swin.edu.au/cosmos/n/neutron+star#:~:text=Neutrons%20stars%20are%20extreme%20objects,weigh%20around%20a%20billion%20tonnes https://astronomy.swin.edu.au/cosmos/n/neutron+star#:~:text=....
- droopyEyelids 5y agoIt would be impossible to put neutron star material inside a cardboard box, and the original post was talking about possibility.
- ben_w 5y agoIf I remember right, given that free neutrons aren’t stable and have a very short half life, it would be explosively unwise even if it was physically possible.
- deepspace 5y agoYes, a free neutron decays to a proton, an electron and an electron neutrino with a half life of 879 seconds. This decay releases 0.8MeV of energy (mostly in the form of kinetic energy of the electron). My back of the envelope calculation shows that 1 gram of neutronium (approximately a mole) will release 43MW of energy continuously. Multiply that by 10^14 (the number of grams of neutronium per teaspoon) and the resultant energy release would be unimaginably huge. 'Explosively' does not even begin to describe it.
- grog454 5y agoActually, it too was talking about impossibility (see title); a much stronger assertion and usually wrong.
- midasuni 5y agoI assume they were saying Densest material on earth There are denser materials, but you would struggle to send them via UPS
- tialaramex 5y agoThis is why simple balances are such a brilliant idea despite their simplicity. You don't need to calibrate to the local conditions, if I have a 250g mass on one side, and I put something on the other side and it balances, that's 250 grams, done. Only the (often provided with the balance) prototype masses need to be calibrated and that can be done by experts far from your local environment. Until as recently as 2019 this approach - using a prototype - was the only extant mass definition, the prototype kilogram lived at a specialised laboratory and its clones were used around the world to define mass (yes including the pound if you're an American). [ Today instead the Planck constant is defined to be exactly 6.62607015×10^−34 kg x m^2 per second and it's possible to build devices such as a Kibble balance to estimate what the kilogram is from knowing this definition, the better your Kibble balance the better the estimate ]