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The critical mass depends on the shape; I don't think there is an upper limit to that.For the case of a sphere, the critical mass for U-235 is 52 kg. The corresponding diameter of the sphere is 17 cm.
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Why is there an upper limit to the mass of neutron stars?
There is an upper limit to the mass of neutron stars because if the neutron star is too massive, neutrons would be crushed by the gravity of the neutron star, and the neutron star would collapse into a black hole.
Is there a limit for the stars?
Yes, there are limits for stars - limits to lower and upper mass, longevity, size, etc. Given the mass of the universe a limit for the number of extant stars would also exist. During stellar collapse at end of a star's life there are some well-studied limits answering to degeneracy pressure, like the Chandresekhar limit, the Oppenheimer-Volkoff limit, etc., which prevent further collapse until a certain mass limit is exceeded (perhaps the last limit being quark degeneracy pressure before further collapse into a black hole). For further examination of a given limit, the limit in question would need to be identified.
How much mass does a planet have?
No lower limit has been formally defined; the lowest-mass accepted planet is Mercury - 0.055 times Earth's mass. The largest planet in our Solar System is Jupiter, at 318 times Earth's mass. Larger planets are known to orbit other stars; the upper limit should be about 13 Jupiter masses or about 4000 Earth masses; an object with more mass than that would be a brown dwarf.
What is the highest degrees in kelvin on earth?
If we could determine the total mass of the universe we might be able to come up with a theoretical upper limit of what is possible, but for all practical purposes the Kelvin scale has no upper limit.
How does mass turn into infinity at the speed of light?
It doesn't - the object will never achieve the speed of light, since an infinite mass is not possible (it would require infinite energy). This only describes a tendency: as the object gets closer and closer to the speed of light, so, too, will its mass increase more and more, approaching infinity - this means there is no upper limit to the mass as the object approaches the speed of light.
Why is there an upper limit to the mass of neutron stars?
There is an upper limit to the mass of neutron stars because if the neutron star is too massive, neutrons would be crushed by the gravity of the neutron star, and the neutron star would collapse into a black hole.
What word is displayed when an object of mass greater than the upper limit is placed on the scale?
Error, maybe!
What are in nuclear bombs?
Enough of either U235 or PU239 to form a critical mass and hence a large explosion
Why is there an upper mass limit for main-sequence stars of about 100 solar masses?
Objects above this mass fuse hydrogen too rapidly and cannot stay together.
About how much many exoplanets have been foun about how big is the biggest one?
As of October 28, 2009 a total of 403 exoplanets have been discovered to date. The mass of an exoplanet is limited by classification. A planet's mass has an upper limit of 13 Jupiter masses as this is the upper limit for an object that can not fuse Deuterium. Any "exoplanet" larger than this limit is generally considered a brown dwarf.
Why is large mass of uranium-235 needed for a chain reaction?
Each time a U235 atom decays, it emits 2-3 neutrons. The likelihood that one of these neutrons is captured by another U235 atom INCREASES with more mass. The SHAPE of this mass will also play a role, imagine a thin wire of U235, compared to a sphere, with regards to how likely a chain reaction will occur. Neutron reflection can also help redirect an errant neutron back into the mass so it can react instead. Compression (increase of density) plays a role as well.
How are isotopes of the same element named?
The same name with a different atomic mass number. As an example U235 and U238 are two isotopes of Uranium
Is there a limit for the stars?
Yes, there are limits for stars - limits to lower and upper mass, longevity, size, etc. Given the mass of the universe a limit for the number of extant stars would also exist. During stellar collapse at end of a star's life there are some well-studied limits answering to degeneracy pressure, like the Chandresekhar limit, the Oppenheimer-Volkoff limit, etc., which prevent further collapse until a certain mass limit is exceeded (perhaps the last limit being quark degeneracy pressure before further collapse into a black hole). For further examination of a given limit, the limit in question would need to be identified.
The concentration of U235 in the atomic bomb?
The references I have state Oralloy is 93.5% U235. Oralloy (Oak Ridge Alloy) was used in US Uranium atomic bombs as the fissile material. However they also say that any enrichment 20% U235 or higher is fissile and could be used to make a bomb, it would require a higher critical mass to work though. One source I have states that early Soviet Uranium atomic bombs used ~97% U235, but the US felt this level of enrichment to be unnecessary and excessively expensive.
Fission is the process of creating energy by?
On nuclear fission, small fraction of mass is loss and transform to energy. The loss mass is part of tiny sub-atomic particle. Consider reaction of Uranium U235 + n1 --> U236 --> Kr92 + Ba141+3n1 Well seem all mass is balance. But take careful step U235 is 235.0439 U236 is 236.0526 Kr92 is 91.92616 Ba141 is 140.9144 n is 1.008665 Some mass was lost and that mass go to energy as Einstein state E = mC2
How much mass does a planet have?
No lower limit has been formally defined; the lowest-mass accepted planet is Mercury - 0.055 times Earth's mass. The largest planet in our Solar System is Jupiter, at 318 times Earth's mass. Larger planets are known to orbit other stars; the upper limit should be about 13 Jupiter masses or about 4000 Earth masses; an object with more mass than that would be a brown dwarf.
What is the highest degrees in kelvin on earth?
If we could determine the total mass of the universe we might be able to come up with a theoretical upper limit of what is possible, but for all practical purposes the Kelvin scale has no upper limit.
