The source of energy in stars is:
The source of energy in stars is primarily nuclear fusion. In the core of stars, hydrogen nuclei (protons) fuse to form helium nuclei, releasing a significant amount of energy in the process. This nuclear fusion reaction powers the star and provides the energy that we observe as light and heat.
If the radioactive decay constant of a radioactive substance is 0.00693 per year, what is the half-life of the substance?
(ln2 = 0.693)
The total decay rate R of a sample is related to the decay rate at t = 0 and the disintegration constant or decay constant λ as:
A nucleus has an atomic number 64. Considering the nucleus as a liquid-drop, its radius will be close to
(= 1.2 fm):
Let N and be the number of radioactive nuclei in a sample at time t and at time t = 0, respectively. Then the ratio () is equal to __________ where λ is the disintegration constant or decay constant.
The total energy released if 47 g of undergoes fission (disintegration energy per event, Q = 200 MeV, Avogadro's number = 6.02 × nuclei/mol) is close to:
A radioactive nucleus emits 3 alpha particles and 2 positrons. For the resultant nucleus, the ratio of neutrons to protons is (consider the initial nucleus to have atomic number Z and atomic mass A):
The half life of a radioactive substance is 10 years and its initial mass is 1 g. The remaining amount after 20 years is ________.
The source of energy in stars is:
Isotopes have the same number of:
When the masses of an electron, proton, and neutron are , and , respectively, then the nuclear mass of an atom is _________.
