In the reaction , if the binding energies of are respectively, a, b and c (in MeV), then the energy (in MeV) released in this reaction is [2005]
In any fission process, the ratio [2005]
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Fission of nuclei is possible because thebinding energy per nucleon in them [2005]
The binding energy of deuteron is 2.2 MeV and that of is 28 MeV. If two deuterons are fused to form one then the energy released is [2006]
In a radioactive material the activity at time t_{1} is R_{1} and at a later time t_{2}, it is R_{2}. If the decay constant of the material is λ, then [2006]
Two radioactive substances A and B have decay constants 5λ and λ respectively. At t = 0 they have the same number of nuclei. The ratio of number of nuclei of A to those of B will be (1/e)^{2} after a time interval [2007]
In a radioactive decay process, the negativelycharged emitted β particles are [2007]
A nucleus ^{A}_{Z}X has mass represented by M (A, Z). If M_{p} and M_{n} denote the mass of proton and neutron respectively and B.E. the binding energy in MeV, then [2007]
If the nucleus has nuclear radius of about 3.6 fm, then would have its radius approximately as [2007]
Two radioactive materials X_{1} and X_{2} have decay constants 5λ and λ respectively. If initially they have the same number of nuclei, then the ratio of the number of nuclei of X_{1} to that of X_{2} will be 1/e after a time
If M (A; Z), M_{p} and M_{n} denote the masses of the nucleus proton and neutron respectively in units of u ( 1u = 931.5 MeV/c^{2}) and BE represents its bonding energy in MeV, then [2008]
Two nuclei have their mass numbers in the ratioof 1 : 3. The ratio of their nuclear densities wouldbe [2008]
In the nuclear decay given below: [2009]
the particles emitted in the sequence are
The mass of a nucleus is 0.042 u less than the sum of the masses of all its nucleons. The binding energy per nucleon of nucleus is nearly
The activity of a radioactive sample is measured as N0 counts per minute at t = 0 and N0/e counts per minute at t = 5 minutes. The time (in minutes) at which the activity reduces to half its value is [2010]
The binding energy per nucleon in deuteriumand helium nuclei are 1.1 MeV and 7.0 MeV,respectively. When two deuterium nuclei fuseto form a helium nucleus the energy released inthe fusion is :
The decay constant of a radio isotope is λ. If A_{1} and A_{2} are its activities at times t_{1} and t_{2} respectively, the number of nuclei which have decayed during the time (t_{1} – t_{2}) :
The half life of a radioactive isotope 'X' is 50 years. It decays to another element 'Y' which isstable. The two elements 'X' and 'Y' were foundto be in the ratio of 1 : 15 in a sample of agiven rock. The age of the rock was estimatedto be [2011]
The power obtained in a reactor using U^{235} disintegration is 1000 kW. The mass decay of U^{235} per hour is [2011]
A radioactive nucleus of mass M emits a photonof frequency μ and the nucleus recoils. The recoilenergy will be [2011]
A nucleus emits one αparticle and two βparticles. The resulting nucleus is [2011]
Fusion reaction takes place at high temperaturebecause [2011]
Two radioactive nuclei P and Q, in a given sample decay into a stable nucleolus R. At time t = 0, number of P species are 4 N_{0} and that of Q are N_{0}. Halflife of P (for conversion to R) is 1 minute where as that of Q is 2 minutes. Initially there are no nuclei of R present in the sample. When number of nuclei of P and Q are equal, the number of nuclei of R present in the sample would be [2011M]
If the nuclear radius of ^{27}Al is 3.6 Fermi, the approximate nuclear radius of ^{64}Cu in Fermi is : [2012]
A mixture consists of two radioactive materials A_{1} and A_{2} with half lives of 20 s and 10 srespectively. Initially the mixture has 40 g of A_{1 }and 160 g of A_{2}. The amount of the two in themixture will become equal after : [2012]
The half life of a radioactive nucleus is 50 days. The time interval (t_{2} – t_{1}) between the time t_{2 }when 2/3 of its has decayed and the time t_{1} when 1/3 of it had decayed is : [2012]
A certain mass of Hydrogen is changed to Heliumby the process of fusion. The mass defect infusion reaction is 0.02866 a.m.u. The energyliberated per a.m.u. is(Given : 1 a.m.u = 931 MeV) [NEET 2013]
The half life of a radioactive isotope ‘X’ is20 years. It decays to another element ‘Y’ whichis stable. The two elements ‘X’ and ‘Y’ were foundto be in the ratio of 1 : 7 in a sample of a thegiven rock. The age of the rock is estimated tobe [NEET 2013]
αparticles, βparticles and γrays are all havingsame energy. Their penetrating power in a givenmedium in increasing order will be [NEET Kar. 2013]
How does the binding energy per nucleon varywith the increase in the number of nucleons ? [NEET Kar. 2013]
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105 videos425 docs114 tests
