Quantrex Academy Quantrex AcademyPYQs with solutions · JEE · NEET · NDA

Home · JEE Main & Advanced · Physics · Nuclear Physics

Nuclear Physics — JEE Main & Advanced Physics PYQs

389 previous year questions from Nuclear Physics with answers and solutions. Numbered list, year tags, and one-tap solutions — built for serious JEE / NEET practice.

389 questionsPhysicsSolutions on every page
1

A nuclear reactor starts producing a radioactive nuclide X from t = 0 , at a constant rate of per second. Each decay of X produces energy E₀ , which is utilized to heat a liquid of

JEE Advanced 2026 Solution View → 2

Two radioactive substances A and B of mass numbers 200 and 212 respectively, shows spontaneous -decay with same Q value of 1 MeV. The ratio of energies of -rays produced by A and B

JEE Main 2026 Solution View → 3

The energy released if hydrogen atoms are combined to form ⁴₂ He is __________ MeV. (Take binding energies per nucleon of ²₁ H and ⁴₂ He as 1.1 MeV and 7.2 MeV, respectively)

JEE Main 2026 Solution View → 4

The energy released when 7 17.13 kg of ⁷₃ Li is converted into ⁴₂ He by proton bombardment is 10³² eV. The value of is _______. (Nearest integer) (Mass of ⁷₃ Li = 7.0183 u, mass of

JEE Main 2026 Solution View → 5

Assuming the experimental mass of ¹²₆C as 12 u , the mass defect of ¹²₆C atom is _______ MeV /c^2 . (Mass of proton = 1.00727 u , mass of neutron = 1.00866 u , 1 u = 931.5 MeV /c^2

JEE Main 2026 Solution View → 6

Two nuclei of mass number 3 combine with another nucleus of mass number 4 to yield a nucleus of mass number 10 . If the binding energy per nucleon for the mass numbers 3 , 4 and 10

JEE Main 2026 Solution View → 7

The binding energy per nucleon of ²⁰⁹₈₃Bi is _______ MeV. [ Take m(²⁰⁹₈₃Bi) = 208.980388 , u, , m_p = 1.007825 , u, , m_n = 1.008665 , u, , 1 , u = 931 , MeV /c^2]

JEE Main 2026 Solution View → 8

A nucleus has mass number and radius R_ . Another nucleus has mass number and radius R_ . If =8 then R_ / R_ is:

JEE Main 2026 Solution View → 9

An atom ₃⁸ X is bombarded by shower of fundamental particles and in 10 s this atom absorbed 10 electrons, 10 protons and 9 neutrons. The percentage growth in the surface area of th

JEE Main 2026 Solution View → 10

The binding energy for the following nuclear reactions are expressed in MeV. ₂ He ³+ ₀ n ¹ ₂ He ⁴+20 MeV ₂ He ⁴+ ₀ n ¹ ₂ He ⁵-0.9 MeV If X ₃, X ₄, X ₅ denote the stability of ₂ He

JEE Main 2026 Solution View → 11

Given below are two statements: Statement I : For all elements, greater the mass of the nucleus, greater is the binding energy per nucleon. Statement II : For all elements, nuclei

JEE Main 2026 Solution View → 12

Which of the following pair of nuclei are isobars of the element?

JEE Main 2026 Solution View → 13

The average energy released per fission for the nucleus of ₉₂²³⁵ U is 190 MeV. When all the atoms of 47 g pure ₉₂²³⁵ U undergo fission process, the energy released is 10²³ MeV . Th

JEE Main 2026 Solution View → 14

The minimum frequency of photon required to break a particle of mass 15.348 amu into 4 particles is _ _ _ _ kHz. [mass of He nucleus = 4.002 amu , 1 amu =1.66 10⁻²⁷ ~kg , ~h =6.6 1

JEE Main 2026 Solution View → 15

7.9 MeV -particle scatters from a target material of atomic number 79. From the given data the estimated diameter of nuclei of the target material is (approximately) _ _ _ _ m. [ 1

JEE Main 2026 Solution View → 16

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

JEE Main 2025 Solution View → 17

Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A) : The density of the copper ( ₂₉⁶⁴ Cu ) nucleus is greater t

JEE Main 2025 Solution View → 18

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 ?

JEE Main 2025 Solution View → 19

Match the List-I with List-II array |l|l|l|l| & List-I & & List-II A. & array l ₀^1 n + ₉₂²³⁵ U ₅₄¹⁴⁰ Xe + ₃₈⁹⁴ Sr +2 ₀^1 n array & I. & array l Chemical reaction array B. & 2 H ₂+

JEE Main 2025 Solution View → 20

Energy released when two deuterons ( ₁ H ^2 ) fuse to form a helium nucleus ( ₂ He ^4 ) is : (Given : Binding energy per nucleon of ₁ H ^2=1.1 MeV and binding energy per nucleon of

JEE Main 2025 Solution View → 21

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

JEE Main 2025 Solution View → 22

Given below are two statements. One is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A) : The binding energy per nucleon is found to be practically

JEE Main 2025 Solution View → 23

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

JEE Main 2025 Solution View → 24

A nucleus at rest disintegrates into two smaller nuclei with their masses in the ratio of 2: 1 . After disintegration they will move :

JEE Main 2024 Solution View → 25

The energy released in the fusion of 2 ~kg of hydrogen deep in the sun is E_H and the energy released in the fission of 2 ~kg of ²³⁵ U is E_U . The ratio E_H E_U is approximately:

JEE Main 2024 Solution View → 26

The energy equivalent of 1 ~g of substance is :

JEE Main 2024 Solution View → 27

A star has 100 % helium composition. It starts to convert three ^4 He into one ¹² C via triple alpha process as ^4 He + ^4 He + ^4 He ¹² C + Q . The mass of the star is 2.0 10³² ~k

JEE Main 2024 Solution View → 28

If M_o is the mass of isotope ₅¹² B, M_P and M_n are the masses of proton and neutron, then nuclear binding energy of isotope is :

JEE Main 2024 Solution View → 29

In a hypothetical fission reaction ₉₂ X²³⁶ ₅₆ Y¹⁴¹+ ₃₆ Z⁹²+3 R The identity of emitted particles ( R ) is :

JEE Main 2024 Solution View → 30

Binding energy of a certain nucleus is 18 10^8 ~J . How much is the difference between total mass of all the nucleons and nuclear mass of the given nucleus:

JEE Main 2024 Solution View → 31

If three helium nuclei combine to form a carbon nucleus then the energy released in this reaction is _____ 10⁻² MeV . (Given 1 u =931 MeV / c ^2 , atomic mass of helium =4.002603 u

JEE Main 2024 Solution View → 32

The disintegration energy Q for the nuclear fission of ²³⁵ U ¹⁴⁰ Ce + ⁹⁴ Zr +n is ______ MeV . Given atomic masses of ²³⁵ U : 235.0439 u ; ¹⁴⁰ Ce : 139.9054 u , ⁹⁴ Zr : 93.9063 u ;

JEE Main 2024 Solution View → 33

Which of the following nuclear fragments corresponding to nuclear fission between neutron ( ₀^1 n ) and uranium isotope ( ₉₂²³⁵ U ) is correct :

JEE Main 2024 Solution View → 34

From the statements given below : (A) The angular momentum of an electron in n t h orbit is an integral multiple of h . (B) Nuclear forces do not obey inverse square law. (C) Nucle

JEE Main 2024 Solution View → 35

The radius of a nucleus of mass number 64 is 4 . 8 fermi. Then the mass number of another nucleus having radius of 4 fermi is 1000 x , where x is _________.

JEE Main 2024 Solution View → 36

The mass number of nucleus having radius equal to half of the radius of nucleus with mass number 192 is:

JEE Main 2024 Solution View → 37

A nucleus has mass number A 1 and volume V 1 . Another nucleus has mass number A 2 and volume V 2 . If relation between mass number is A 2 = 4 A 1 , then V 2 V 1 = _______.

JEE Main 2024 Solution View → 38

In a nuclear fission reaction of an isotope of mass M , three similar daughter nuclei of same mass are formed. The speed of a daughter nuclei in terms of mass defect Δ M will be :

JEE Main 2024 Solution View → 39

The explosive in a Hydrogen bomb is a mixture of H 2 1 , H 3 1 and Li 6 3 in some condensed form. The chain reaction is given by Li 6 3 + n 1 0 → He 4 2 + H 3 1 ; H 2 1 + H 3 1 → H

JEE Main 2024 Solution View → 40

The atomic mass of C 12 6 is 12 . 000000 u and that of C 13 6 is 13 . 003354 u . The required energy to remove a neutron from C 13 6 , if mass of neutron is 1 . 008665 u , will be:

JEE Main 2024 Solution View → 41

In a nuclear fission process, a high mass nuclide ( A ≈ 236 ) with binding energy 7 . 6 MeV / Nucleon dissociated into two middle mass nuclides ( A ≈ 118 ) , having binding energy

JEE Main 2024 Solution View → 42

In a radioactive decay process, the activity is defined as A = - d N d t , where N ( t ) is the number of radioactive nuclei at time t . Two radioactive sources, S 1 and S 2 have s

JEE Advanced 2023 Solution View → 43

List- I shows different radioactive decay processes and List- II provides possible emitted particles. Match each entry in List- I with an appropriate entry from List- II , and choo

JEE Advanced 2023 Solution View → 44

The half-life of a radioactive nucleus is 5 years. The fraction of the original sample that would decay in 15 years is :

JEE Main 2023 Solution View → 45

Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R Assertion A : The binding energy per nucleon is practically independent of the

JEE Main 2023 Solution View → 46

92 238 A → 90 234 B + D 2 4 + Q In the given nuclear reaction, the approximate amount of energy released will be: [Given, mass of 92 238 A = 238 . 05079 × 931 . 5 MeV c

JEE Main 2023 Solution View → 47

A common example of alpha decay is 238 92 U → 234 90 Th + 2 He 4 + Q Given: 238 92 U = 238 . 05060   u 234 90 Th = 234 . 04360   u 4 2 He = 4 . 00260   u and 1

JEE Main 2023 Solution View → 48

Two radioactive elements A and B initially have same number of atoms. The half life of A is same as the average life of B . If λ A and λ B are decay constants of A and B

JEE Main 2023 Solution View → 49

The half life of a radioactive substance is T . The time taken, for disintegrating 7 8 t h part of its original mass will be:

JEE Main 2023 Solution View → 50

The decay constant for a radioactive nuclide is 1 . 5 × 10 - 5 s - 1 . Atomic weight of the substance is 60 g mole - 1 , N A = 6 × 10 23 . The activity of 1 . 0 µ g

JEE Main 2023 Solution View → 51

A radio active material is reduced to 1 8 of its original amount in 3 days. If 8 × 10 - 3 kg of the material is left after 5 days the initial amount of the material is

JEE Main 2023 Solution View → 52

For a nucleus X Z A having mass number A and atomic number Z A. The surface energy per nucleon ( b s ) = – a 1 A 2 3 . B. The Coulomb contribution to the binding energy b c =

JEE Main 2023 Solution View → 53

A nucleus with mass number 242 and binding energy per nucleon as 7 . 6   MeV breaks into two fragment each with mass number 121 . If each fragment nucleus has binding energy p

JEE Main 2023 Solution View → 54

If the binding energy of ground state electron in a hydrogen atom is 13 . 6 eV , then, the energy required to remove the electron from the second excited state of Li 2 + will be: x

JEE Main 2023 Solution View → 55

A free neutron decays into a proton but a free proton does not decay into neutron. This is because

JEE Main 2023 Solution View → 56

Given below are two statements : one is labelled as Assertion A and the other is labelled as Reason R Assertion A : The nuclear density of nuclides B 5 10 , L 3 6 i , F 26 56 e , N

JEE Main 2023 Solution View → 57

A radioactive nucleus decays by two different process. The half life of the first process is 5 minutes and that of the second process is 30 s . The effective half-life of the nucle

JEE Main 2023 Solution View → 58

Substance A has atomic mass number 16 and half life of 1 day. Another substance B has atomic mass number 32 and half life of 1 2 day. If both A and B simultaneously start undergo r

JEE Main 2023 Solution View → 59

If a radioactive element having half-life of 30 min is undergoing beta decay, the fraction of radioactive element remains undecayed after 90 min will be :

JEE Main 2023 Solution View → 60

A radioactive element X 92 242 emits two α -particles, one electron and two positrons. The product nucleus is represented by Y P 234 . The value of P is ______.

JEE Main 2023 Solution View → 61

The ratio of the density of oxygen nucleus O 8 16 and helium nucleus He 2 4 is

JEE Main 2023 Solution View → 62

The energy released per fission of nucleus of X 240 is 200 MeV . The energy released if all the atoms in 120 g of pure X 240 undergo fission is _____ × 10 25 MeV . (Given N A

JEE Main 2023 Solution View → 63

Consider the following radioactive decay process: A 84 218 ⟶ α A 1 ⟶ β - A 2 ⟶ γ A 3 ⟶ α A 4 ⟶ β + A 5 ⟶ γ A

JEE Main 2023 Solution View → 64

Assume that protons and neutrons have equal masses. Mass of a nucleon is 1 . 6 × 10 - 27 kg and radius of nucleus is 1 . 5 × 10 - 15 A 1 3 m . The approximate ratio of th

JEE Main 2023 Solution View → 65

In a radioactive decay chain reaction, 90 230 Th nucleus decays into Po 84 214 nucleus. The ratio of the number of α to number of β - particles emitted in this process is

JEE Advanced 2022 Solution View → 66

The minimum kinetic energy needed by an alpha particle to cause the nuclear reaction N 7 16 + He 2 4 → H 1 1 + O 8 19 in a laboratory frame is n (in MeV ). Assume that N 7 16

JEE Advanced 2022 Solution View → 67

The binding energy of nucleons in a nucleus can be affected by the pairwise Coulomb repulsion. Assume that all nucleons are uniformly distributed inside the nucleus. Let the bindin

JEE Advanced 2022 Solution View → 68

Two radioactive materials A and B have decay constants 25 λ and 16 λ respectively. If initially they have the same number of nuclei, then the ratio of the number of nucle

JEE Main 2022 Solution View → 69

A radioactive sample decays 7 8 times its original quantity in 15 minutes. The half-life of the sample is

JEE Main 2022 Solution View → 70

The half life period of a radioactive substance is 60 days. The time taken for 7 8 th of its original mass to disintegrate will be :

JEE Main 2022 Solution View → 71

A freshly prepared radioactive source of half life 2 hours 30 minutes emits radiation which is 64 times the permissible safe level. The minimum time, after which it would be possib

JEE Main 2022 Solution View → 72

The activity of a radioactive material is 6 . 4 × 10 - 4 curie. Its half life is 5 days. The activity will become 5 × 10 - 6 curie after

JEE Main 2022 Solution View → 73

What is the half-life period of a radioactive material if its activity drops to 1 16 th of its initial value of 30 years ?

JEE Main 2022 Solution View → 74

Mass numbers of two nuclei are in the ratio of 4 : 3 . Their nuclear densities will be in the ratio of

JEE Main 2022 Solution View → 75

Two lighter nuclei combine to form a comparatively heavier nucleus by the relation given below: X 1 2 + X 1 2 = Y 2 4 The binding energies per nucleon X 1 2 and Y 2 4 are 1 . 1 MeV

JEE Main 2022 Solution View → 76

The disintegration rate of a certain radioactive sample at any instant is 4250 disintegrations per minute. 10 minutes later, the rate becomes 2250 disintegrations per minute. The a

JEE Main 2022 Solution View → 77

In the following nuclear reaction, D → α D 1 → β - D 2 → α D 3 → γ D 4 Mass number of D is 182 and atomic number is 74 . Mass number and

JEE Main 2022 Solution View → 78

The half life of a radioactive substance is 5 years. After x years a given sample of the radioactive substance gets reduced to 6 . 25 % of its initial value. The value of x is ____

JEE Main 2022 Solution View → 79

The activity of a radioactive material is 2 . 56 × 10 - 3 Ci . If the half life of the material is 5 days, after how many days the activity will become 2 × 10 - 5 Ci ?

JEE Main 2022 Solution View → 80

Following statements related to radioactivity are given below : (A) Radioactivity is a random and spontaneous process and is dependent on physical and chemical conditions. (B) The

JEE Main 2022 Solution View → 81

The Q -value of a nuclear reaction and kinetic energy of the projectile particle, K p are related as

JEE Main 2022 Solution View → 82

A radioactive nucleus can decay by two different processes. Half-life for the first process is 3 . 0 hours while it is 4 . 5 hours for the second process. The effective halflife of

JEE Main 2022 Solution View → 83

How many alpha and beta particles are emitted when Uranium U 92 238 decays to lead Pb 82 206 ?

JEE Main 2022 Solution View → 84

A sample contains 10 - 2 kg each of two substances A and B with half lives 4 s and 8 s respectively. The ratio of their atomic weights is 1 : 2 . The ratio of the amounts of A and

JEE Main 2022 Solution View → 85

Nucleus A is having mass number 220 and its binding energy per nucleon is 5 . 6 MeV . It splits in two fragments B and C of mass numbers 105 and 115 . The binding energy of nucleon

JEE Main 2022 Solution View → 86

A heavy nucleus N , at rest, undergoes fission N → P + Q , where P and Q are two lighter nuclei. Let δ = M N - M P - M Q , where M P , M Q and M N are the masses of P ,

JEE Advanced 2021 Solution View → 87

A heavy nucleus Q of half-life 20 minutes undergoes alpha-decay with probability of 60 % and beta-decay with probability of 40 % . Initially, the number of Q nuclei is 1000 . The n

JEE Advanced 2021 Solution View → 88

The half life period of a radioactive element x is same as the mean life time of another radioactive element y . Initially they have the same number of atoms. Then:

JEE Main 2021 Solution View → 89

A sample of a radioactive nucleus A disintegrates to another radioactive nucleus B , which in turn disintegrates to some other stable nucleus C . Plot of a graph showing the variat

JEE Main 2021 Solution View → 90

There are 10 10 radioactive nuclei in a given radioactive element. Its half-life time is 1 min . How many nuclei will remain after 30 s ? ( 2 = 1 . 414 )

JEE Main 2021 Solution View → 91

At time t = 0 , a material is composed of two radioactive atoms A and B , where N A ( 0 ) = 2 N B ( 0 ) The decay constant of both kind of radioactive atoms is λ . However, A

JEE Main 2021 Solution View → 92

Consider the following statements: A . Atoms of each element emit characteristics spectrum. B . According to Bohr's Postulate, an electron in a hydrogen atom revolves in a cert

JEE Main 2021 Solution View → 93

If f denotes the ratio of the number of nuclei decayed N d to the number of nuclei at t = 0 , N 0 then for a collection of radioactive nuclei, the rate of change of f with respect

JEE Main 2021 Solution View → 94

A radioactive sample has an average life of 30 ms and is decaying. A capacitor of capacitance 200 μ F is first charged and later connected with resistor R . If the ratio of th

JEE Main 2021 Solution View → 95

From the given data, the amount of energy required to break the nucleus of aluminium Al 13 27 is __________ x × 10 - 3   J Mass of neutron = 1 . 00866   u Mass of pr

JEE Main 2021 Solution View → 96

The nuclear activity of a radioactive element becomes 1 8 th of its initial value in 30 years. The half-life of radioactive element is ________ years.

JEE Main 2021 Solution View → 97

Some nuclei of a radioactive material are undergoing radioactive decay. The time gap between the instances when a quarter of the nuclei have decayed and when half of the nuclei hav

JEE Main 2021 Solution View → 98

The half-life of Au 198 is 3 days. If atomic weight of Au 198 is 198 g mol - 1 , then the activity of 2 mg of Au 198 is [in disintegration second - 1 ]:

JEE Main 2021 Solution View → 99

A nucleus with mass number 184 initially at rest emits an α - particle. If the Q value of the reaction is 5 . 5 MeV , calculate the kinetic energy of the α - particle.

JEE Main 2021 Solution View → 100

For a certain radioactive process, the graph between ln R and t ( sec ) is obtained as shown in the figure. Then the value of half life for the unknown radioactive material is appr

JEE Main 2021 Solution View → 101

A radioactive substance decays to 1 16 th of its initial activity in 80 days. The half life of the radioactive substance expressed in days is ________.

JEE Main 2021 Solution View → 102

A radioactive material decays by simultaneous emissions of two particles with half lives of 1400 years and 700 years, respectively. What will be the time after the which one third

JEE Main 2021 Solution View → 103

A nucleus of mass M emits γ -ray photon of frequency v . The loss of internal energy by the nucleus is: [Take c as the speed of electromagnetic wave]

JEE Main 2021 Solution View → 104

The decay of a proton to neutron is :

JEE Main 2021 Solution View → 105

A radioactive sample disintegrates via two independent decay processes having half lives T 1 / 2 ( 1 ) and T 1 / 2 ( 2 ) respectively. The effective half- life T 1 / 2 of the nucle

JEE Main 2021 Solution View → 106

The half-life of Au 198 is 2 . 7 days. The activity of 1 . 50 mg of Au 198 , if its atomic weight is 198 g mol - 1 is, N A = 6 × 10 23 mol - 1

JEE Main 2021 Solution View → 107

Calculate the time interval between 33 % decay and 67 % decay if half-life of a substance is 20 min .

JEE Main 2021 Solution View → 108

A radioactive sample is undergoing α decay, At any time t 1 , its activity is A and another time t 2 , the activity is A 5 . What is the average life time for the sample ?

JEE Main 2021 Solution View → 109

Two radioactive substances X and Y originally have N 1 and N 2 nuclei respectively. Half life of X is half of the half life of Y . After three half lives of Y , number of nuclei of

JEE Main 2021 Solution View → 110

Given the masses of various atomic particles m P = 1 , 0072   u , m n = 1 , 0087   u , m e = 0 .000548   u , m v ¯ = 0 , m d = 2 .0141   u , where p =

JEE Main 2020 Solution View → 111

You are given that Li 3 7 = 7 . 0160 u , Mass of Mass of He 2 4 = 4 . 0026 u and Mass of He 1 1 = 1 . 0079 H When 20 g of Li 3 7 is converted into 2 4 He by proton capture, the ene

JEE Main 2020 Solution View → 112

A radioactive nucleus decays by two different processes. The half-life for the first process is 10 s and that for the second is 100 s . The effective half-life of the nucleus is cl

JEE Main 2020 Solution View → 113

Activities of three radioactive substances A , B and C are represented by the curves A , B and C , in the figure. Then their half-lives T 1 2 A : T 1 2 B : T 1 2 C are in the ratio

JEE Main 2020 Solution View → 114

Find the Binding energy per nucleon for Sn 50 120 . Mass of proton m p = 1 . 00783 U , mass of neutron m n = 1 . 00867 U and mass of tin nucleus m sn = 119 . 902199 U . (take 1 U =

JEE Main 2020 Solution View → 115

The radius R of a nucleus of mass number A can be estimated by the formula R = 1 . 3 × 10 - 15 A 1 / 3 m . It follows that the mass density of n nucleus is of the order of: M

JEE Main 2020 Solution View → 116

In a radioactive material, a fraction of active material remaining after the time t i s 9 16 . The fraction that was remaining after the time t 2 is :

JEE Main 2020 Solution View → 117

The activity of a radioactive sample falls from 700 s - 1 to 500 s - 1 in 30 minutes. Its half life is close to:

JEE Main 2020 Solution View → 118

Half-life of radioactive substance is 3 .20 h . What is the time taken for 75% of substance to be used?

NTA Abhyas JEE Main 2020 Solution View → 119

The energy spectrum of β - p a r t i c l e s [number N E as a function of β - energy E ] emitted from a radioactive source is

NTA Abhyas JEE Main 2020 Solution View → 120

The mean lives of a radioactive substance are 1620 years and 405 years for α and β emission respectively. If it is decaying by both α and β emission simultaneously, then the time d

NTA Abhyas JEE Main 2020 Solution View →
Practice all Nuclear Physics questions in the app →