The Half Life Of 131I Is 8 Days. Give A Sample Of 131I At Time T = O, We Can Assert That

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The half life of 131I is 8 days. Give a sample of 131I at time t = o, we can assert that


Correct option is

A given nucleus may decay at any time after t = o

Number of nuclie  decereases enponentially


Decay process lasts upto t = ∞, a nucleus may decay at any time after t = 0



Calculate the binding energy per nucleon of the nuclei of Given :mass of hydrogen atom = 1.007825 u, mass of neutron = 1.008665 u, mass of  atom = 55.934939 u, mass of  atom = 208.980388u and . Which nucleus is more stable?


The binding energy energies of deuteron  and -particle  are 1.112 and 7.07 MeV/nucleon respectively. Find out in the process , state whether energy is supplied or liberated and how much? 


A heavy nucleus X of mass number A = 240 and binding energy per nucleon = 7.6 MeV is split into two nearly equal fragments Y and Z of mass numbers A1 = 110 and A2 = 130. The binding energy of each one of these nuclei is 8.5 MeV per nucleon. Calculate the total binding energy of each of the nuclei XY and Z, and hence the energy Q released per fission in MeV.   



The neutron separation energy is defined to be the energy required to remove a neutron from a nucleus. Obtain the neutron separation energy of the nucleus of Given : mass of  atom = 40.962278 u, mass of  atom = 39.962591 u, mass of neutron = 1.008665 u and .   


The nucleus  decays by -emission. Write down the decay equation and determine the maximum kinetic energy of the emitted electron. The atomic masses of  are 22.994466 u and 22.989770 u respectively.


When a deuteron  of mass 2.0141 u and negligible kinetic energy is absorbed by a lithium  nucleus of mass 6.0155 u, the compound nucleus disintegrates spontaneously into two alpha particles, each of mass 4.0026 u. Calculate the energy in joule carried by each alpha particle.    


If the half lives of a radioactive element for α and β decay are 4 yrs and 12 yrs respectively, the ratio of their activities after six yrs will be


Half life of a radioactive sulistance A is 4 days. The probability that a nucleus will dacay in two half lives is


The half life of  The time taken for the radioactivity of a sample of  to dacay to 1/6 th  of its initial value is:


The mass of one mole of electrons is