Nuclei-Quiz-2

NUCLEI QUIZ-2

Dear Readers,

JEE Advanced Physics Syllabus can be referred by the IIT aspirants to get a detailed list of all topics that are important in cracking the entrance examination. JEE Advanced syllabus for Physics has been designed in such a way that it offers very practical and application-based learning to further make it easier for students to understand every concept or topic by correlating it with day-to-day experiences. In comparison to the other two subjects, the syllabus of JEE Advanced for physics is developed in such a way so as to test the deep understanding and application of concepts.

Q1. After 280 days, the activity of a radioactive sample is 6000 dps. The activity reduces to 3000dps after another 140 days. The initial activity of the sample(in dps) is

•  a)6000
•  b)9000
•  c)3000
•  d)24000

Solution

Q2.  The binding energies per nucleon of deuteron ( _1 H^2) and helium ( _2 He^4) atoms are 1.1 MeV and 7 MeV. If two deuteron atoms react to form a single helium atom, then the energy released is

•  a) 13.9 MeV 
•  b)26.9 MeV
•  c)23.9 MeV
•  d)19.2 MeV

Solution

Q3. In the options given below, let E denote the rest mass energy of a nucleus and n a neutron. the correct option is

•   a)E((_92^236)U) > E((_53^137)I) + E((_39^97)Y) + 2E(n)
•  b)E((_92^236)U)
•  E((_92^236)U) >E((_56^140)Ba) + E((_36^94)Kr) + 2E(n)
•  E((_92^236)U)

Solution

Q4. N_1 atoms of a radioactive element emit N_2 beta particles per second. The decay constant of the element is (in s^(-1))

•  a)N_1/N_2
•  b)N_2/N_1
•  c)N_1 ln⁡〖(2)〗
•  d)N_2 ln⁡〖(2)〗

Solution

Q5. The binding energy of an electron in the ground state of He-atom is E_0=24.6 eV. The energy required to remove both the electrons from the atom is

•  a)24.6 eV
•  b)79.0 eV
•  c)54.4 eV
•  d)None of these

Solution

Q6. 16. A nucleus〖 _ ^ 〗_Z^A X emits an α-particle. The resultant nucleus emits a β^+ particle. The respective atomic and mass numbers of the final nucleus will be

•  a)Z-3,A-4
•  b)Z-1,A-4
• c)Z-2,A-4
•  d)Z,A-2

Solution

Q7. Order of magnitude of density of uranium nucleus is [m_p=1.67×10^(-27) kg]

•  a)10^20 kg m^(-3)
•  b)10^17 kg m^(-3)
•  c)10^14 kg m^(-3)
•  d)10^11 kg m^(-3)

Solution

Q8. The half-life period of a radioactive element X is same as the mean lifetime of another radioactive element Y. Initially, both of them have the same number of atoms. Then,

•  a)X and Y have the same decay rate initially
•  b)X and Y decay at the same rate always
•  c)Y will decay at a faster rate than X ²
•  d)X will decay at a faster rate than Y³

Solution

Q9. A newly prepared radioactive nuclide has a decay constant λ of 10^(-6) s^(-1). What is the approximate half-life of the nuclide?

•  a)1 hour
•  b)1 day
•  c)1 week
•  d)1 month

Solution

Q10. A star initially has 10^40 deuterons. It produces energy via the processes _1^2 H+ _1^2 H→ _1^3 H+p and _1^2 H+ _1^3 H→ _2^4 H+n If the average power radiated by the star is 10^16 W, the deuteron supply of the star is exhausted in a time of the order of [Given: M( _ ^2 H)=2.014 u,M(n)=1.008 u,M(p)=1.008 u and M( _ ^4 He)=4.001 u]

•  a)10^6 s
•  b)10^8 s
•  c)10^12 s
• d)10^16 s

Solution