**NUCLEI QUIZ-10**

**NUCLEI QUIZ-10**

**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.

**Q1The electron emitted in beta radiation originates from**

Solution

(c)
We know that in a nucleus, neutron converts into proton as follows:
n→p^+→e^-
Thus, decay of neutron is responsible for Î²-radiation orgination

**Q2The minimum frequency of a Î³-ray that causes a deuteron to disintegrate into a proton and a neutron is (m_d=2.0141 a.m.u.,m_p=1.0078 a.m.u.,m_n=1.0087 a.m.u)**

**Q3Let E_1 and E_2 be the binding energies of two nuclei A and B. It is observed that two nuclei of A combine together to form a B nucleus. This observation is correct only if**

Solution

(c)
Transformation occurs only when the same net energy is released, which is possible only when E_2>2E_1

**Q4If mass of 〖 _ U〗^235=235.12142 a.m.u., mass of 〖 _ U〗^236=236.1205 a.m.u. and mass of neutron =1.008665 a.m.u., then the energy required to remove one neutron from the nucleus of 〖 _ U〗^236 is nearly about**

**Q6. The energy released in a typical nuclear fusion reaction is approximately**

Solution

**Q7. Mark out the incorrect statement**

Solution
(a)
When a free neutron decays to a proton along with an electron and an antineutrino, the Q value of the reaction is positive which means the reaction is possible all by itself, while a free proton cannot convert itself into a neutron due to negative Q value
In beta minus decay, the electron originates from nucleus only, by the transformation of neutron into a proton, with simultaneous emission of an antineutrino

**Q8 For uranium nucleus how does its mass vary with volume?**

Solution

(a)
Nuclear density is constant hence, mass ∝ volume
Or m∝ V

**Q9An element X decays, first by positron emission and then two Î±-particles are emitted in successive radioactive decay. If the product nucleus has a mass number 229 and atomic number 89, the mass number and atomic number of element X are**

**Q10. At any instant, the ratio of the amounts of two radioactive substances is 2:1. If their half-lives be, respectively, 12 h and 16 h, then after two days, what will be the ratio of the substances?**