Nucleus Questions and Answers

Q No 4 View In English Energy released in the fission of a single g2u235 nucleus is 200 MeV The fission rate of a g2u235 fuelled reactor operating at a power level of 5W is 1 2 3 156 10 10 1 156 10 1 156 10 16 1 156 x 10 17 1 plete Question Content Correct Answer 2 Status unattempted Close atom tion W

Callium arsenide phosphide is a semiconducting material having energy band gap of 2 eV if the band gap is incresed to 3 eV the wavelength will be OPTIONS 5123 Angstrom

15 The critical volume of a gas is 0 072 lit mol The radius of the molecule will be in cm 1 10 23 X 2 10 2 10 3 16 X

Suppose an alpha particle accelerated by a potential of V volt is allowed to collide with a nucleus whose atomic number is Z then the distance of closest approach of alpha particle to the nucleus is a 14 4 b 14 4 c 1 44 A d 14 4

A positron with kinetic energy 1 MeV and an electron with kinetic energy 1MeV meet each ot moving in opposite directions They annihilate each other by emitting two photons If the rest energy of an electron is 0 51 MeV the wavelength of each photon is A 5 1 10 B 10 2 10 C 8 2 10 D 6 2 10

5 5 An isolated hydrogen atom emits a photon of 10 2 eV recoil speed of hydrogen atom A 3 25 m s B 3 m s D 1 m s C 6 2 m s A circular coil of 100 turns and effective diameter 20 cm caries a current of 1A It is to turned in a magne

1 Show that the mass defect of the nuclear reaction 1BeB e is given as 4 ush oda Serai do atomic mass of B Be whereas for the B Be e is given as Am atomic mass of 19 Am reaction 8 n 8 5 8D

0 A rigid tank contains 35 kg of nitrogen at 6 atm Sufficient quantity of oxygen is supplied to increase the pressure to 9 atm while the temperature remains constant Amount of oxygen supplied to the tank is 1 5 kg bas 3 20 kg uistomer bris 2 10 kg 4 4 40 kg 40 kg

A radioactive nucleus ZXA emit 3a particles and 53 particles The ratio of number of neutrons to that of protons in the product nucleus will be Question Type Single Correct Type 1 2 3 4 A Z 12 Z 6 A Z Z 1 A Z 11 Z 6 A Z 11 71

200 MeV of energy can be obtained by per fission in reactor generating 1000 kW Find the number of nuclei undergoing the fission per second Question Type Single Correct Type 1 1000 2 2 108 3 3 125 x 1016

Half life period of two elements are 30 minute and 20 minute respectively then after one hour ratio of the remaining nuclei will be Initially both have equal active nuclei Question Type Single Correct Type 1 4 1 2 1 2 3 8 1

The wavelength of a photon is 4 times of an electron The speed of the electron is V C then 100 ratio of energy of electron to that of photon is Question Type Single Correct Type 1 10 2 2 2 10 2 3 4 x 10 2

7 In Rutherford scattering experiment what will be the correct angle for a scattering for an impact parameter b 0 CBSE PMT 1994 JIPMER 2000 Gujarat CET 2007 a 90 c 0 b 270 d 180

Choose the incorrect statement The nuclear force between two nucleons falls rapidly to zero as their distance is more than few fm Potential energy between two nucleons is minimum at distance about 0 8 fm III Nuclear force is attractive for distances larger than 0 8 fm Nuclear force is unsaturated force

Consider an arrangement of a biprism and screen as shown in the figure The refracting angle of the biprism is A 20 and the refractive index of its material is 1 5 The wavelength of the monochromatric light emitted from the source is 6000 Find the fringe width of the interference pattern obtained on the screen Source Biprism 25cm A 100cm Scr

For nuclear fusion choose incorrect statement In fusion two lighter nuclei combine to form a larger nucleus In fusion a heavy nucleus breaks into two smaller nucleus Fusion of hydrogen nuclei into helium nuclei is the source of energy of sun For thermonuclear fusion enough kinetic energy is required to overcome the coulombic repulsion

X rays are emitted by a tube containing the element Niobium Z 41 as anti cathode and the K x rays are allowed to be incident on an unknown gas containing hydrogen like ions It is found that the X rays cause the emission of photoelectrons with an energy of 2 7 keV from these ions Mark CORRECT options A the minimum voltage at which the x ray tube should be operated so that the momentum of the emitted photoelectrons is doubled is approx 24 5 kV B the approximate value of Z for the target of the anticathode after the momentum has been doubled is 50 using screening constant C the approximate value of the atomic number of the atoms of the gas is 32 using screening constant D the number of gas ions produced is approx 850 ions per second per m caused by X rays is if the intensity of X rays is 100 mW m and 1 of the X rays cause ionization

Block A of mass 1 kg is hanging at rest from a vertical spring of spring constant k 600 N m Block B of 1 kg mass strikes the block A with velocity v and sticks to it Then the value of v for which the spring just attains natural length is A 10 m s B 1 m s m A ml B c m s D None of these F

2 In a CE transistor amplifier the audio signal voitage across the collector resistance of 2kQ is 2V If the base resistance is 1kQ and the current amplification of the transistor is 100 the input signal voltage is a 0 1V b 1 0V c 1mV 2012 d 10 mV

Assuming that about 20 MeV of energy is released per fusion reaction H H He E other particles Then the mass of H consumed per day in fusion reactor of power 10 MW will be nearly 1 8 g 0 1 g 10 g

A nuclear explosion is designed with a nuclear fuel consisting of U 235 to run a reactor to deliver 1 MW of heat energy The amount of energy released per fission is 200 MeV Find the amount of U 235 needed to run this reactor for one year

4 In the options given below let E denote the rest mass energy of a nucleus and n a neutron The correct option is 1 E U E I E Y 2E n 2 E U E 1 E Y 2E n 3 E U E Ba E Kr 2E n E U E Ba E Kr E n 4

The above is a plot of binding energy per nucleon Eb against the nuclear mass M A B C D E correspond to different nuclei Consider four reactions i A B C ii C A B iii D E F iv F D E where is the energy released In which reactions positive Eo BCD E F

1 Binding energy per nucleon versus mass number curve for nuclei is shown in the figure W X Y and Z are four nuclei indicated on the curved The process that would release energy is a Y 2Z c W2Y BE nucleon in MeV 8 5 8 0 7 5 5 0 Z Y X W 30 60 90 120 Mass number of nuclei b W X Y d X Y Z

The curve of binding energy per nucleon as a function of atomic mass number has a sharp peak for helium nucleus This implies that helium a can easily be broken up b is very stable c can be used as fissionable material d is radioactive on nuclear reaction A B C D and E represents

The number of beta particles emitted by a radioactive substance is twice the number of alpha particles emitted by it The resulting daughter is an 2009 a isomer of parent b isotone of parent c isotope of parent d isobar of parent

c 60 days d 15 days 87 A certain mass of Hydrogen is changed to Helium by the process of fusion The mass defect in fusion reaction is 0 02866 a m u The energy liberated per a m u is Given 1 a m u 931 MeV a 26 7 MeV c 13 35 MeV NEET 2013 6 675 MeV b d 2 67 MeV

49 If M A Z M and M denote the of the nucleus masses AX proton and neutron respectively in units of u 1 u 931 5 MeV c and BE represents its binding energy in MeV then a M A Z ZM A Z M BE b M A Z ZM A Z M BE c c M A Z ZM A Z M BE c d M AZ ZM A Z M BE

A nuclear reactor of 500 MW rating is used for a nuclear fusion reaction 2H H He If the energy from the above reaction is used with 25 efficiency in the reactor how many grams of deuterium fuel will be needed I per day masses of H and H are 2 0141 and 4 0026 u respectively 3

Additional Materials EeBook 4 Points DETAILS MY NOTES 30 0 ASK YOUR TEACHER A small plastic ball with a mass of 6 45 x 10 3 kg and with a charge of 0 138 C is suspended from an insulating thread and hangs between the plates of a capacitor see the drawing The ball is in equilibrium with the thread making an angle of 30 0 with respect to the vertical The area of each plate is 0 0139 m What is the magnitude of the charge on each plate C PRACTICE ANOTHER

Obtain the mass defect in amu and binding energy in MeV for the Fe nucleus What is the binding energy in MeV per nucleor Symbol Z A Mass amu 10 n P Fe 0 1 1 1 26 56 0 000549 1 008665 1 00728 5 93494 Mass defect Binding energy Binding energy per nucleon amu MeV MeV nucleon

2 The kinetic energy of a particle emitted in the a decay of 88 Ra 226 is given mass number of Ra 222 u a 5 201 MeV c 6 023 MeV UP CPMT 2015 b 3 301 MeV d 4 871 MeV

c energy e energy production in stars Kerala CEE 20 d 1 1 The approximate ratio of nuclear mass densities of 197 Au and 107 Ag nuclei is 47 79 a 197 107 b 47 79 c 79 47 e 107 197 element X disintegrates successively

3 The half life of a radioactive isotope X is 20 yr It decays to another element Y which is stable The two elements X and Y were found to be in the ratio 1 7 in a sample of a given rock The age of the rock is estimated to be a 40 yr b 60 yr c 80 yr NEET 2013 d 100 yr

7 If the nuclear force between two protons two neutrons and between proton and neutron is denoted by Fpp Fnn and Fpn respectively then a Fpp Enn Fpn PP b Fpp Fnn and F c Fpp Fnn Fpn d Fnn Fpn PP Fnn PP 1991

The number of particles emitted by a radioactive substance is twice the number of a particles emitted by it The resulting daughter is an NCERT Pg 450 1 Isomer of parent 2 Isotone of parent 3 Isobar of parent 4 Isotope of parent

Two nuclei fuse together to form a single nucleus as A AB If binding energy per nucleon of A and B are respectively x and y then the energy released in the process is 1 4x 4y 2 4x 4y 3 4y 4x 4 y x

of one 14 A nucleus ruptures into two nuclear parts which have their velocity ratio equal to 2 1 What will be the ratio of their nuclear size nuclear radius 1 2 31 2 1 2 3 3 3 21

c The masses of neutron and proton are 1 0087 amu and 1 0073 amu respectively If the neutrons and protons combine to form a helium nucleus alpha particles of mass 4 0015 amu the binding energy of the helium nucleus will be 1 amu 931 MeV a 28 4 MeV b 20 8 MeV c 27 3 MeV d 14 2 MeV 6 a 236 92 ny per nucleon of X and Y is 8 5 MeV whereas of 236 tol energy liberated will be about

Example 13 6 Calculate the energy required to remove the leas 40 tightly bound neutron in Ca Given that 20 Mass of 20 Ca 40 39 962589 amu Mass of 20 Ca 39 38 970691 amu Mass of neutron 1 008665

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 U E 31 E Y 2E n 53 236 92 39 E 26U E 31 E Y 2E n 92 39 B C E 236 U E 140Ba E Kr 2E n 92 36 D E 236U E 40 Ba E Kr 2E n 92 97 53 56

13 A diatomic gas molecule consists of two atoms of mass m separated by a fixed distance d and rotating about an axis as indicated in the figure Assuming that its angular momentum is quantized as in the Bohr atom Determine a The possible angular velocities b The possible quantized rotational energies m E

Which one of the following statements about uranium is correct a 235 U is fissionable by thermal neutrons b Fast neutrons trigger the fission process in 235 U c 235 U breaks up into fragments when bombarded by slow neutrons d 235 U is an unstable isotope and undergoes spontaneous fission

Slightly greater than T Consider a nuclear reaction A A A3 A4 If B B B3 and B4 are the binding energie of the nuclei A A A3 and A4 respectively which of the following condition will b applicable for the process to be exoergic 1 B3 B4 B B 2 B3 B4 B B 3 B B B3 B4 0 LA D D 2

92 In a fission reaction 236 U 117X 117Y n n the binding energy per nucleon of X and Y is 8 5MeV whereas of 236U is 7 6 MeV The total energy liberated will be about Question Type Single Correct Type 1 200 KEV 2 2 MeV 3 200 MeV

Magnetic moment of an electron in nth orbit of hydrogen atom is neh a c m meh 2 n b neh 4m meh d 59 4tn m mass of electron h Planck s constant dedi

An alpha particle is projected from infinity w ith a velocity V alpha towards the nucleus of an atom having atomic number Z Find i C losest distance of approach R ii The velo city of the alpha particle at the distance R1 R1 R from the nucleus

Identify the incorrect relationship 2 r 2 2 Number of revolutions of an electron per Vn 2 r 1 Number of waves in an orbit n second in nth orbit n 3 Wavelength of an electron slo p 4 Speed of a de Broglie wavelength particle accelerated by a potential difference V is 2eV

65 In the given nuclear reaction A B C D E represent 92 U 238aBZADYC92X234 a A 234 B 90 C 234 D 91 e b A 234 B 90 C 238 D 94 e a c A 238 B 93 C 234 D 91 e d A 234 B 90 C 234 D 93 e a A radioactive nucleus undergoes a series of deca

Two radioactive substances A and B whose half lives are 2 years and 8 years respectively Initially 80 gm of A and 20 gm of B is taken The time after which they will have same quantity remaining is 1 6 years 1215 23 2 6 22 years 4 4 45 years