X PHYSICS
UNIT – X
MODERN PHYSICS
1. Atom of an element is electrically ______________.
2. Rutherford’s gold-foil experiment led to the discovery of ____________.
3. Matter is made of tiny indivisible ____________.
4. The atom of one element is different from the ____________ of any other element. 5. Electrons in an atom was first established by ____________.
6. Electrons are negatively ____________ particles.
7. Rutherford’s atomic model failed to explain the ____________ of an atom.
8. Nuclear size is nearly ____________ smaller than that of atom.
9. The space between the nucleus and the electrons is largely ____________.
10. Stationary orbits do not radiate ____________.
11. The ____________ has a definite energy in a stationary orbit.
12. Bohr’s model of atom is based on ____________.
13. The space between electron and proton is ____________.
14. ____________ is positively charged particle.
15. The radius of the nucleus of an atom is less than ____________ meters.
16. amu stands for ____________.
17. Neutron is electrically ____________.
18. The amu is defined as 1/12th of the mass of a neutral____________.
19. According to Einstein mass energy relation E = ____________.
20. 1 Kg mass = ____________ Joules.
21. Atomic number is also called____________as number.
22. Protons are also equal to the number of ____________ in a neutral atom.
23. The atomic number (Z) of carbon is ____________.
24. The atomic number of hydrogen is ____________.
25. Mass of one neutron is ____________.
26. ____________ force is responsible for the stability of a nucleus.
27. The relation between mass and energy conversion was postulated by ____________.
28. Mass and energy are mutually ____________.
29. The principal mass energy equivalence is given by ____________.
30. The disintegration of an unstable nucleus resulting in another nucleus is called ________.
31. The mass of ß-particle is the same as the mass of ____________.
32. The atomic number of an atom ____________ when a ß particle is emitted.
33. Two different elements having same number of neutrons are called ____________.
34. Ionising power is highest in the case of ____________.
35. Isobars are the elements with ____________.
36. A ?-decay causes ____________ in mass number by ____________ units. 37. Radioactivity was discovered by ____________.
38. The uranium ore is ____________.
39. ? particle is a doubly ionized ____________ atom.
40. The mass of ?-particle is ____________ times the mass of proton.
41. ?- particles have small ____________ power.
42. ß-particles are electrons originating in the ____________.
43. The speed of ß particles is ____________.
44. The speed of light is ____________.
45. ß particles cause scintillations on a ____________ material.
46. ?-rays are ____________ radiations.
47. The penetrating power of ____________ is more than that ? and ß particles.
48. ? – rays can be easily destroy human ____________.
49. ____________ rays are not deflected by electric and magnetic fields.
50. Thorium series are represented by ____________ series.
51. The most radioactive element is ____________.
52. ?-rays are emitted by the ____________ nucleus in radioactivity.
53. The end product of Neptunium series is ____________.
54. Radon is an ____________ gas.
55. Radioactivity decay is ____________ in nature.
56. Neptunium series is known as ____________.
57. The scientist who discovered the isotopes for neon is ____________.
58. 1 Ao = ____________.
59. Bismith series is a ____________.
60. ____________ reactions takes place in stars.
X PHYSICS
UNIT – X
PHYSICS ( Key )
(1) neutral (2) proton (3) particles (4) atom (5) Thomson (6) charged (7) stability (8) One lakh times (9) empty (10) energy (11) electron (12) Planck’s quantum theory (13) vacuum (14) proton (15) 2.4 × 10–15 (16) atomic mass unit (17) neutral (18) carbon (19) ?mc2 (20) 9 ×1016 (21) proton (22) electrons (23) 6 (24) 1 (25) 1.0087 a.m.u (26) nuclear (27) Albert Einstein (28) convertible (29) E = ? mc2 (30) radio active transformation. (31) electron (32) increases by one unit (33) isotones (34) ?-particles (35) same mass number (36) decrement, 4 (37) Becquerel (38) pitch blend (39) helium (40) four (41) penetrating (42) nucleus (43) 108 m/s (44) 3 × 108 m/s (45) fluorescent (46) electro magnetic (47) ?-rays (48) cells (49) ? (50) 4n (51) Radium (52) parent (53) Bismith (54) inert (55) exponential (56) (4n+1) series (57) Thomson (58) 10–8 cm (59) 4n+1 (60) fusion.
