Nuclei

For a nucleus of mass number A and radius R, the mass density of nucleus can be represented as

1. A 23
2. Independent of A
3. A3
4. A 13

Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R). In the light of the above statements, choose the most appropriate answer from the options given below :

1. (A) is correct but (R) is not correct
2. Both (A) and (R) are correct but (R) is not the correct explanation of (A)
3. (A) is not correct but (R) is correct
4. Both (A) and (R) are correct and (R) is the correct explanation of (A)

A radioactive material P first decays into Q and then Q decays to non-radioactive material R. Which of the following figure represents time dependent mass of P, Q and R ?

1. [figure]
2. [figure]
3. [figure]
4. [figure]

Match the LIST-I with LIST-II Choose the correct answer from the options given below:

1. A-II, B-I, C-III, D-IV
2. A-III, B-I, C-II, D-IV
3. A-III, B-I, C-IV, D-II
4. A-II, B-I, C-IV, D-III

Energy released when two deuterons (1H2 ) fuse to form a helium nucleus (2He4 ) is : (Given : Binding energy per nucleon of 1H2 = 1.1 MeV and binding energy per nucleon of 2He4 = 7.0 MeV)

1. 26.8 MeV
2. 8.1 MeV
3. 23.6 MeV
4. 5.9 MeV

Choose the correct nuclear process from the below options [p : proton, n : neutron, e- : electron, e+ : positron, : neutrino, : antineutrino]

1. n p + e+ +
2. n p + e- +
3. n p + e+ +
4. n p + e- +

A radioactive nucleus n2 has 3 times the decay constant as compared to the decay constant of another radioactive nucleus n1. If initial number of both nuclei are the same, what is the ratio of number of nuclei of n2 to the number of nuclei of n1, after one half-life of n1 ?

1. 1/4
2. 1/8
3. 4
4. 8

Given below are two statements. One is labelled as Assertion (A) and the other is labelled as Reason (R). In the light of the above statements, choose the correct answer from the options given below :

1. (A) is true but (R) is false
2. Both (A) and (R) are true and (R) is the correct explanation of (A)
3. (A) is false but (R) is true
4. Both (A) and (R) are true but (R) is NOT the correct explanation of (A)

The energy equivalent of 1 g of substance is :

1. 5.6 1026 MeV
2. 5.6 1012 MeV
3. 5.6 eV
4. 11.2 1024 MeV

A star has 100\% helium composition. It starts to convert three 4He into one 12C via triple alpha process as 4He + 4He + 4He 12C + Q. The mass of the star is 2.0 1032 kg and it generates energy at the rate of 5.808 1030 W. The rate of converting these 4He to 12C is n 1042 s-1, where n is . [Take, mass of 4He = 4.0026 u, mass of 12C = 12 u]