`K`-capture
a. Refers to capture by other nucleus of an electron from `K`-shell
b. Results in decrease in `Z`
c. Is of the type
`._(56)Ba^(133) + ._(-1)e^(0) rarr ._(55)Cs^(133) _ gamma`-rays d. All of these

In the disintegration of a radioactive element, alpha - and beta -particles are evolved from the nucleus. ._(0)n^(1) rarr ._(1)H^(1) + ._(-1)e^(0) + Antineutrino + Energy 4 ._(1)H^(1) rarr ._(2)He^(4) + 2 ._(+1)e^(0) + Energy Then, emission of these particles changes the nuclear configuration and results into a daughter nuclide. Emission of an alpha -particles results into a daughter element having atomic number lowered by 2 and mass number by 4, on the other hand, emission of a beta -particle yields an element having atomic number raised by 1. A radioactive element belongs to III B group, it emits ona alpha - and beta -particle to form a daughter nuclide. The position of daughter nuclide will be in

Scientists are working hard to develop nuclear fusion reactor Nuclei of heavy hydrogen, _(1)^(2)H , known as deuteron and denoted by D , can be thought of as a candidate for fusion rector . The D-D reaction is _(1)^(2) H + _(1)^(2) H rarr _(2)^(1) He + n+ energy. In the core of fusion reactor, a gas of heavy hydrogen of _(1)^(2) H is fully ionized into deuteron nuclei and electrons. This collection of _1^2H nuclei and electrons is known as plasma . The nuclei move randomly in the reactor core and occasionally come close enough for nuclear fusion to take place. Usually , the temperature in the reactor core are too high and no material will can be used to confine the to plasma for a time t_(0) before the particles fly away from the core. If n is the density (number volume ) of deuterons , the product nt_(0) is called Lawson number. In one of the criteria , a reactor is termed successful if Lawson number is greater then 5 xx 10^(14) s//cm^(2) it may be helpfull to use the following boltzmann constant lambda = 8.6 xx 10^(-5)eV//k, (e^(2))/(4 pi s_(0)) = 1.44 xx 10^(-9) eVm Result of calculations for four different design of a fusion reactor using D-D reaction are given below. which of these is most promising based on Lawson criterion ?

Scientists are working hard to develop nuclear fusion reactor Nuclei of heavy hydrogen, _(1)^(2)H , known as deuteron and denoted by D , can be thought of as a candidate for fusion rector . The D-D reaction is _(1)^(2) H + _(1)^(2) H rarr _(2)^(1) He + n+ energy. In the core of fusion reactor, a gas of heavy hydrogen of _(1)^(2) H is fully ionized into deuteron nuclei and electrons. This collection of _1^2H nuclei and electrons is known as plasma . The nuclei move randomly in the reactor core and occasionally come close enough for nuclear fusion to take place. Usually , the temperature in the reactor core are too high and no material will can be used to confine the to plasma for a time t_(0) before the particles fly away from the core. If n is the density (number volume ) of deuterons , the product nt_(0) is called Lawson number. In one of the criteria , a reactor is termed successful if Lawson number is greater then 5 xx 10^(14) s//cm^(2) it may be helpfull to use the following boltzmann constant lambda = 8.6 xx 10^(-5)eV//k, (e^(2))/(4 pi s_(0)) = 1.44 xx 10^(-9) eVm In the core of nucleus fusion reactor , the gas become plasma because of

Scientists are working hard to develop nuclear fusion reactor Nuclei of heavy hydrogen, _(1)^(2)H , known as deuteron and denoted by D , can be thought of as a candidate for fusion rector . The D-D reaction is _(1)^(2) H + _(1)^(2) H rarr _(2)^(1) He + n+ energy. In the core of fusion reactor, a gas of heavy hydrogen of _(1)^(2) H is fully ionized into deuteron nuclei and electrons. This collection of _1^2H nuclei and electrons is known as plasma . The nuclei move randomly in the reactor core and occasionally come close enough for nuclear fusion to take place. Usually , the temperature in the reactor core are too high and no material will can be used to confine the to plasma for a time t_(0) before the particles fly away from the core. If n is the density (number volume ) of deuterons , the product nt_(0) is called Lawson number. In one of the criteria , a reactor is termed successful if Lawson number is greater then 5 xx 10^(14) s//cm^(2) it may be helpfull to use the following boltzmann constant lambda = 8.6 xx 10^(-5)eV//k, (e^(2))/(4 pi s_(0)) = 1.44 xx 10^(-9) eVm In the core of nucleus fusion reactor , the gas become plasma because of

Scientists are working hard to develop nuclear fusion reactor Nuclei of heavy hydrogen, _(1)^(2)H , known as deuteron and denoted by D , can be thought of as a candidate for fusion rector . The D-D reaction is _(1)^(2) H + _(1)^(2) H rarr _(2)^(1) He + n+ energy. In the core of fusion reactor, a gas of heavy hydrogen of _(1)^(2) H is fully ionized into deuteron nuclei and electrons. This collection of _1^2H nuclei and electrons is known as plasma . The nuclei move randomly in the reactor core and occasionally come close enough for nuclear fusion to take place. Usually , the temperature in the reactor core are too high and no material will can be used to confine the to plasma for a time t_(0) before the particles fly away from the core. If n is the density (number volume ) of deuterons , the product nt_(0) is called Lawson number. In one of the criteria , a reactor is termed successful if Lawson number is greater then 5 xx 10^(14) s//cm^(2) it may be helpfull to use the following boltzmann constant k = 8.6 xx 10^(-5)eV//k, (e^(2))/(4 pi s_(0)) = 1.44 xx 10^(-9) eVm Assume that two deuteron nuclei in the core of fusion reactor at temperature energy T are moving toward each other, each with kinectic energy 1.5 kT , when the seperation between them is large enough to neglect coulomb potential energy . Also neglate any interaction from other particle in the core . The minimum temperature T required for them to reach a separation of 4 xx 10^(-15) m is in the range

Scientists are working hard to develop nuclear fusion reactor Nuclei of heavy hydrogen, _(1)^(2)H , known as deuteron and denoted by D , can be thought of as a candidate for fusion rector . The D-D reaction is _(1)^(2) H + _(1)^(2) H rarr _(2)^(1) He + n+ energy. In the core of fusion reactor, a gas of heavy hydrogen of _(1)^(2) H is fully ionized into deuteron nuclei and electrons. This collection of _1^2H nuclei and electrons is known as plasma . The nuclei move randomly in the reactor core and occasionally come close enough for nuclear fusion to take place. Usually , the temperature in the reactor core are too high and no material will can be used to confine the to plasma for a time t_(0) before the particles fly away from the core. If n is the density (number volume ) of deuterons , the product nt_(0) is called Lawson number. In one of the criteria , a reactor is termed successful if Lawson number is greater then 5 xx 10^(14) s//cm^(2) it may be helpfull to use the following boltzmann constant lambda = 8.6 xx 10^(-5)eV//k, (e^(2))/(4 pi s_(0)) = 1.44 xx 10^(-9) eVm Assume that two deuteron nuclei in the core of fusion reactor at temperature energy T are moving toward each other, each with kinectic energy 1.5 kT , when the seperation between them is large enough to neglect coulomb potential energy . Also neglate any interaction from other particle in the core . The minimum temperature T required for them to reach a separation of 4 xx 10^(-15) m is in the range

When nucleus of an electrically neutral atom undergoes a radioactive decay process, it will remain neutral after the decay if the process is (a) An alpha - decay (b) A beta^(o+) -decay (c ) A gamma -decay (d) A K - capture process

Unstable nuclei attain stability through disintegration. The nuclear stability is related to neutron proton ratio (n//p) . For stable nuclei n//p ratio lies close to unity for elements with low atmoic numbers (20 or less) but it is more than 1 for nuclei having higher atomic numbers. Nuclei having n//p ratio either very high or low undergo nuclear transformation. When n//p ratio is higher than required for stability, the nuclei have the tendency to emit beta -rays. while when n//p ratio is lower than required for stability, the nuclei either emits alpha -particles or a positron or capture K -electron. For reaction ._(92)M^(238) rarr ._(y)N^(x) + 2 ._(2)He^(4), ._(y)N^(x) rarr ._(B)L^(A) + 2 ._(-1)e^(0) The number of neutrons in the element L is

A radioactive nuclide emits gamma -rays due to a. K-electron capture b. Nuclear transition from higher to lower energy c. Presence of greater number of neutrons than protons d. Presence of greater of protons than neutrons

X-ray are emitted by a tube containing the electron gt Noibum (Z = 41) as anticathode and the K_(alpha) X-ray an allowed to be incident on an unknown gas containing hydrogen- like atom ions. It is found that the X-ray cause the emission of photoelectrons with an energy of 2.7 keV from these ions. Find a. the minimum voltage at which the X-ray tube should be opreated so that the momentum of the emitted photoelectrons is doubled. b. the approximate value of Z for the target of the anticathode after the momentum has been doubled. c. the approximate value of Z the atomic number of the atom of the gas. d. the number of the ion produced in the gas caused by X-ray , if the inetensity of X-ray is 100 mWm^(-2) and 1% of the X-rays cause ionization.