46: important feature of pion is that it has
a) Finite energy
b) Infinite energy
c) Finite range
d) Infinite range
47: in radioactive equilibrium no. of atom of each number element in directly proportional to
its
a) Average life
b) Half life
c) Rate of formation
d) Rate of disintegration
48: in Van De Graff generator accelerator the potential V develop at the top terminal with respect to ground is
a) V/R
b) V/I
c) R/C
d) Q/C
49: to impart high energy in F.M cyclotron the orbits of the ions needs to be
a) Magnetized
b) Expanded
c) Energized
d) Stabilized
50: a certain radioactive element has a half-life of 120d the time it will take for 7/8 of the atomic originally present to disintegrate is
a) 80d
b) 20d
c) 40d
d) 60d
51: in betatron the magnetic flux density is B at
a) Central region
b) Air gap
c) Constant radius
d) Annular tube
52: in neutral atom, the electrons are bound to the nucleus by
a) Magnetic force
b) Electrostatic force
c) Friction force
d) Centripetal force
53: force on the electron acceleration in an accelerator under the action of electric field is
a) F = qB
b) F = eB
c) F =Ee
d) F – EB
54: A 100g sample of a radioactive element has a half-life of 5 days, how many grams of radioactive material will remain after 15days?
a) 100g
b) 50g
c) 25g
d) 12.5g
55: the correct expression relating the energy E of a particle to its rest mass m0, its moment p, and the speed of light c, is.
a) E2= p2c2 + m0c2
b) E2 = p2c2 + (m0c)2
c) E2 = p2c + (m0c2)2
d) E2 = p2c2 + (m0c2)
56: which of the following is correct for the number of neutrons in the nucleus?
a) N = Z-A
b) N = A
c) N = A-Z
d) N = Z-A
57: Rapid and continues exchange of mesons between nucleus is responsible for
a) Nuclear force
b) Pions
c) Photons
d) Conservation of energy
58: an isotope with a high binding energy per nucleon
a) Will decay and short period of time
b) Has very few electrons
c) Is very unstable
d) Is very stable
59: how many protons and in the 7 14N atoms?
a) 6
b) 7
c) 9
d) 10
60: nucleus “a” contains 5 protons and 5 neutrons and has radius R, the radius of nucleus “b”which contains 35 protons and 45 neutrons is closes to
a) 2R
b) R
c) 4R
d) 8R
61: average life period of disintegrating atom is inversely proportional to
a) Wavelength
b) Half life
c) Radioactive constant
d) Total number of atoms
62: in liquid drop model the symmetry effect is known to be inversely proportional to
a) A + 2Z
b) A – 2Z
c) Atomic number
d) Mass number
63: how many nucleuses are in the 10 20Ne atom
a) 10
b) 20
c) 18
d) 38
64: the most developed nuclear model is
a) Collective model
b) Shell model
c) Liquid drop model
d) None of these
65: emission of nucleons is analogous to ….. of molecules
a) Division
b) Emission
c) Formation
d) Evaporation
66: the velocity of electrons in betatron at 300 Mev is nearly
a) 0.99C
b) 0.98C
c) > 1 C
d) < 0.98C
67:3 The relation between the De Broglie and Bohr’s theory
a) Energy
b) Momentum
c) nħ= ⋋P
d) none of these
68: Radius of Bohr’s r=?
a) αon2
b) αon3
c) αon
d) None of these
69: what are the value of stationary states if <A>t=5 =5 what will be <A>t=10 =?
a) 5
b) 10i + 5
c) 10
d) 15
70: when waves are combine the add?
a) No. of particles
b) Amplitude
c) Intensities
d) None of these
