Atoms PYQs Set 15 (PDF)

Set 15 of 16 · Questions 421-450 of 453

In the print window choose “Save as PDF”. The file prints without a web address or date line.

Mere Teacher · Previous Year Questions JEE Main Physics · Atoms · Set 15 (Q421-450)
Scan or visit mereteacher.com for free PYQ practice, timed CBT tests, step-by-step solutions and BroBot AI. Answers and solutions are free with a sign-up.
421. $The graph which depicts the results of Rutherford gold foil experiment with α-particles is: α-particles is: Y = Number of scattered α-particles detected (Plots are schematic and not to scale)$ (1) (2) (3) (4) 422. $The most penetrating radiation out of the following are$ (1) $β ‐rays$ (2) $γ ‐rays$ (3) $X ‐rays$ (4) $α ‐rays$ 423. $The mass of proton, neutron and helium nucleus are respectively 1.0073 u, 1.0087 u and 4.0015u. The binding energy of helium nucleus is:$ (1) $142 MeV$ (2) $28.4MeV$ (3) $56.8 MeV$ (4) $7.1 MeV$ 424. $Which rays contain (positive) charged particles?$ (1) $α ‐rays$ (2) $β ‐rays$ (3) $γ ‐rays$ (4) $X ‐rays.$ 425. $Nucleus A is having mass number 220 and its binding energy per nucleon is 5.6 MeV. It splits in two fragments^{'} B^{^{'}} and 'C' of mass numbers 105 and 115. The binding energy of nucleons in ' B^{^{'}} and 'C' is 6.4 MeV per nucleon. The energy Q released per fission will be:$ (1) $0.8 MeV$ (2) $275 MeV$ (3) $220 MeV$ (4) $176 MeV$ 426. $Which source is associated with a line emission spectrum?$ (1) $Electric fire$ (2) $Neon street sign$ (3) $Red traffic light$ (4) $Sun$ 427. $The constituents of atomic nuclei are believed to be$ (1) $neutrons and protons$ (2) $protons only$ (3) $electron and protons$ (4) $electrons, protons and neutrons$ 428. $In a Ruby laser, the colour of laser light is due to atom.$ (1) $oxygen$ (2) $aluminium$ (3) $xenon$ (4) $chromium$ 429. $2 α - particle consists of$ (1) $2 protons only$ (2) $2 protons and 2 neutrons only$ (3) $2 electrons, 2 protons and 2 neutrons$ (4) $2 electrons and 4 protons only$ 430. $Number N of the α particles deflected in Rutherford a scattering experiment varies with the angle of deflection θ . Then the graph between the two is best represented by.$ (1) (2) (3) (4) 431. $Hydrogen atoms are excited from ground state of the principle quantum number 4. Then the number of spectral lines observed will be$ (1) $3$ (2) $6$ (3) $5$ (4) $2$ 432. $The ground state energy of hydrogen atom is ‐13.6 eV . When its electron is in the first excited state, its excitation energy is$ (1) $10.2 eV$ (2) $0$ (3) $3.4 eV$ (4) $6.8 eV$ 433. $In a radioactive decay chain, the initial nucleus is_{90}^{232} Th . At the end there are 6 α -particles and 4 β -particles which are emitted. If the end nucleus is_{Z}^{A} X, A and Z are given by :$ (1) $A = 202; Z = 80$ (2) $A = 208; Z = 80$ (3) $A = 200; Z = 81$ (4) $A = 208; Z = 82$ 434. $How many alpha and beta particles are emitted when Uranium_{92} U^{238} decays to lead_{82} P b^{206} ?$ (1) $3 alpha particles and 5 beta particles$ (2) $6 alpha particles and 4 beta particles$ (3) $4 alpha particles and 5 beta particles$ (4) $8 alpha particles and 6 beta particles$ 435. $The explosive in a Hydrogen bomb is a mixture of_{1} H^{2},_{1} H^{3} and_{3} Li^{6} in some condensed form. The chain reaction is given by_{3} Li^{6} +_{0} n^{1} \to_{2} He^{4} +_{1} H^{3}_{1} H^{2} +_{1} H^{3} \to_{2} He^{4} +_{0} n^{1} During the explosion the energy released is approximately [Given : M (Li) = 6.01690 amu, M (H^{2}) = 2.01471 amu, M (_{2} He^{4}) = 4.00388 amu, and 1 amu = 931.5 MeV]$ (1) $28.12 MeV$ (2) $12.64 MeV$ (3) $16.48 MeV$ (4) $22.22 MeV$ 436. $Positron is the antiparticle of$ (1) $proton$ (2) $electron$ (3) $neutron$ (4) $photon$ 437. $α-particle consists of:$ (1) $2 protons only$ (2) $2 protons and 2 neutrons only$ (3) $2 electrons, 2 protons and 2 neutrons$ (4) $2 electrons and 4 protons only$ 438. $The atomic number of silicon is 14. Its ground state electron configuration is$ (1) $1 s^{2} 2 s^{2} 2 p^{2} 2 s^{4}$ (2) $1 s^{2} 2 s^{2} 2 p^{6} 3 s^{1} 3 p^{3}$ (3) $1 s^{2} 2 s^{2} 2 p^{8} 3 s^{2}$ (4) $1 s^{2} 2 s^{2} 2 p^{6} 3 s^{2} 3 p^{2}$ 439. $In Bohr's atomic model of hydrogen, let K. P and E are the kinetic energy, potential energy and total energy of the electron respectively. Choose the correct option when the electron undergoes transitions to a higher level:$ (1) $All K. P and E increase.$ (2) $K decreases. P and E increase.$ (3) $P decreases. K and E increase.$ (4) $K increases. P and E decrease.$ 440. $From the statements given below:(A) The angular momentum of an electron in orbit is an integral multiple of h.(B) Nuclear forces do not obey inverse square law.(C) Nuclear forces are spin dependent.(D) Nuclear forces are central and charge independent.(E) Stability of nucleus is inversely proportional to the value of packing fraction.Choose the correct answer from the options given below:$ (1) $(A), (B), (C), (D) only$ (2) $(A), (C), (D), (E) only$ (3) $(A), (B), (C), (E) only$ (4) $(B), (C), (D), (E) only$ 441. $In Rutherford experiment, for head-on collision of α -particles with a gold nucleus, the impact parameter is$ (1) $of the order of 10^{- 10} m$ (2) $zero$ (3) $of the order of 10^{- 6} m$ (4) $of the order of 10^{- 14} m$ 442. $The transition from the state n = 3 to n = 1 in a hydrogen like atom results in ultraviolet radiation. Infrared radiation will be obtained in the transition from$ (1) $2 \to 1$ (2) $3 \to 2$ (3) $4 \to 2$ (4) $4 \to 3$ 443. $Due to earth’s magnetic field, the charged cosmic rays particles$ (1) $can never reach the pole$ (2) $can never reach the equator$ (3) $require greater kinetic energy to reach the equator than pole$ (4) $require less kinetic energy to reach the equator than pole.$ 444. $Which one of the following is NOT correct?$ (1) $In forward biased condition diode conducts.$ (2) $If the packing fraction is negative, the element is stable.$ (3) $Binding energy is the energy equivalent to mass defect.$ (4) $Radioactive element can undergo spontaneous fission.$ 445. $The scientist who is credited with the discovery of 'nucleus' in an atom is$ (1) $Niels Bohr$ (2) $Rutherford$ (3) $J.J. Thomson$ (4) $Balmer$ 446. $The number of spectral lines emitted by atomic hydrogen that is in the 4^{th} energy level, is$ (1) $3$ (2) $1$ (3) $6$ (4) $0$ 447. $Consider the following radioactive decay process_{84}^{218} A α A_{1} β^{-} A_{2} γ A_{3} α A_{4} β^{+} A_{5} γ A_{6} The mass number and the atomic number A_{6} are given by:$ (1) $210 and 82$ (2) $210 and 84$ (3) $210 and 80$ (4) $211 and 80$ 448. $In a photoelectric effect experiment, the graph of stopping potential V versus reciprocal of wavelength obtained is shown in the figure. As the intensity of incident radiation is increased$ (1) $Slope of the straight line get more steep$ (2) $Graph does not change$ (3) $Straight line shifts to left$ (4) $Straight line shifts to right$ 449. $A radioactive material P first decays into Q and then Q decays to non-radioactive material R . Which of the following figure represents time dependent mass of P, Q and R ?$ (1) (2) (3) (4) 450. $A radioactive element_{92}^{242} X emits two α -particles, one electron and two positrons. The product nucleus is represented by_{P}^{234} Y . The value of P is$