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In the sample, there are N nuclei of X and 5N nuclei of Y. The half-life of isotope X is half of that of isotope Y. Y is not the product of X decaying nor is X the product of Y decaying.
The sample is stored for a time equal to two half-lives of isotope Y.
Determine the magnitude of the ratio
at the end of the storage period.
(3 marks)
b Polonium-210 is an alpha particle emitter with a decay constant of 5.80 × 10−8 s−1.
i Complete the decay equation below.
(2 marks)
ii Calculate the activity of 1.80 mg of polonium-210.
(3 marks)
iii How many nuclei of the polonium remain after 98 days?
cobalt-60 weighing 1 g in units of Curie (Ci).
D-De fusion only needs one million degrees to ignite. and so is used to explore fusion in experimental reactors. I read that in a protostar, it doesn’t get much hotter, but http://hyperphysics.phy-astr.gsu.edu/hbase/NucEne/fusion.html says it produces 3.27 MeV or 4.03 MeV, producing an He-3 or a tritium.
If D-D is easy, why isn’t it explored for fusion power? Not enough energy, or is the cross section (likelihood of a reaction?) too low, or?
3.27 MeV = ~38 billion degrees kelvin: 4.02 = 47 billion. Assume you could fuse a D-D plasmoid (by inducing a current and so a field-reverse configuration “pinch” in it? Could that be enough?)—and you then slammed two or more D- He-3 plasmoids on top of that at thousands of km/sec; could the D-D fusion act as the “spark” to ignite the D + He-3 and He-3 + He-3?
If you then slammed protons on top of that, and crushed it all down with an external magnetic field, do you think you might ignite proton-proton fusion?
See: “nuclear fusion: deuterium–tritium fusion produces neutrons of 14.1 MeV (1400 TJ/kg, i.e. 52,000 km/s, 17.3% of the speed of light) that can easily fission uranium-238 and other non-fissile actinides.” Here:
https://en.wikipedia.org/wiki/Neutron_temperature#Fast
Doesn’t “non-fissile” mean under all circumstances?
https://www.translatorscafe.com/unit-converter/en-US/energy/10-70/megaelectron-volt-kelvin/
https://en.wikipedia.org/wiki/Neutron_temperature#Fast
Answer: (2πmq^4)/(€²h^3)
#340153 on Dec 2023