Advertisements
Advertisements
प्रश्न
The mass of a neutral carbon atom in ground state is
विकल्प
exact 12 u
less than 12 u
more than 12 u
depends on the form of carbon such as graphite of charcoal.
Advertisements
उत्तर
exact 12 u
In nuclear physics, a unit used for measurement of mass is unified atomic mass unit, which is denoted by u.
It is defined such that
1 u = `1/12 xx` (Mass of neutral carbon atom in its ground state)
Mass of neutral carbon atom in its ground state = 12 × 1 u = 12 u
Thus, the mass of neutral carbon atom in its ground state is exactly 12 u.
APPEARS IN
संबंधित प्रश्न
Calculate and compare the energy released by a) fusion of 1.0 kg of hydrogen deep within Sun and b) the fission of 1.0 kg of 235U in a fission reactor.
In a typical fission reaction, the nucleus is split into two middle-weight nuclei of unequal masses. Which of the two (heavier or lighter) has greater kinetic energy? Which one has greater liner momentum?
If three helium nuclei combine to form a carbon nucleus, energy is liberated. Why can't helium nuclei combine on their own and minimise the energy?
The heavier nuclei tend to have larger N/Z ratio because
(a) a neutron is heavier than a proton
(b) a neutron is an unstable particle
(c) a neutron does not exert electric repulsion
(d) Coulomb forces have longer range compared to the nuclear forces.
As the mass number A increases, which of the following quantities related to a nucleus do not change?
Calculate the energy released by 1g of natural uranium assuming 200 MeV is released in each fission event and that the fissionable isotope 235U has an abundance of 0.7% by weight in natural uranium.
Calculate the Q-value of the fusion reaction 4He + 4He = 8Be. Is such a fusion energetically favourable? Atomic mass of 8Be is 8.0053 u and that of 4He is 4.0026 u.
(Use Mass of proton mp = 1.007276 u, Mass of `""_1^1"H"` atom = 1.007825 u, Mass of neutron mn = 1.008665 u, Mass of electron = 0.0005486 u ≈ 511 keV/c2,1 u = 931 MeV/c2.)
Calculate the energy that can be obtained from 1 kg of water through the fusion reaction 2H + 2H → 3H + p. Assume that 1.5 × 10−2% of natural water is heavy water D2O (by number of molecules) and all the deuterium is used for fusion.
(Use Mass of proton mp = 1.007276 u, Mass of `""_1^1"H"` atom = 1.007825 u, Mass of neutron mn = 1.008665 u, Mass of electron = 0.0005486 u ≈ 511 keV/c2,1 u = 931 MeV/c2.)
A town has a population of 1 million. The average electric power needed per person is 300 W. A reactor is to be designed to supply power to this town. The efficiency with which thermal power is converted into electric power is aimed at 25%. (a) Assuming 200 MeV to thermal energy to come from each fission event on an average, find the number of events that should take place every day. (b) Assuming the fission to take place largely through 235U, at what rate will the amount of 235U decrease? Express your answer in kg per day. (c) Assuming that uranium enriched to 3% in 235U will be used, how much uranium is needed per month (30 days)?
Which particle is most likely to be captured by a 235u nucleus and cause it to undergo fission?
Distinguish between nuclear fission and fusion giving an example of each.
How long can an electric lamp of 1000 W be kept glowing by fusion of 2.0 kg of deuterium? Take the fusion reaction as:
\[{}_{1}^{2}\mathrm{H}+_{1}^{2}\mathrm{H}\rightarrow{}_{2}^{3}\mathrm{He}+\mathrm{n}+3.27\mathrm{MeV}\]
In a nuclear reactor, moderators slow down the neutrons which come out in a fission process. The moderator used have light nuclei. Heavy nuclei will not serve the purpose because ____.
Power generated by a nuclear reactor is given by P = n E / t. Here n represents:
\[\ce{^290_80X ->[\alpha] Y ->[e+] Z ->[\beta-] P ->[e-] Q}\]
In the nuclear emission stated above, the mass number and atomic number of the product Q respectively, are:
