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M.C.Q (1 Marks)

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41 questions · auto-graded multiple-choice test.

MCQ 21 Mark
Half-life of radioactive substance is :
  • A
    $0.6931 \times \lambda$
  • B
    $\frac{\log 10^2}{\lambda}$
  • $\frac{0.6931}{\lambda}$
  • D
    $\frac{\text { Average age }}{0.6931}$
Answer
Correct option: C.
$\frac{0.6931}{\lambda}$
C
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MCQ 31 Mark
Density of nucleus is about :
  • A
    $2.29 \times 10^7 kg m ^{-3}$
  • B
    $2.29 \times 10^{-7} kg m ^{-3}$
  • $2.29 \times 10^{17} kg m ^{-3}$
  • D
    $2.29 \times 10^{-17} kg m ^{-3}$
Answer
Correct option: C.
$2.29 \times 10^{17} kg m ^{-3}$
C
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MCQ 41 Mark
1 amu (u) is equivalent to :
  • A
    $1.66 \times 10^{-27} g$
  • $1.66 \times 10^{-27} kg$
  • C
    $1.66 \times 10^{-27} mg$
  • D
    $1.66 \times 10^{-27} MeV$
Answer
Correct option: B.
$1.66 \times 10^{-27} kg$
B
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MCQ 51 Mark
The least stable nucleus is :
  • ${ }_2^4 He$
  • B
    ${ }_6^{12} C$
  • C
    ${ }_8^{16} O$
  • D
    ${ }_{26}^{56} Fe$
Answer
Correct option: A.
${ }_2^4 He$
A
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MCQ 61 Mark
$\gamma$-rays are similar to :
  • A
    $\alpha$-rays
  • B
    $\beta$-rays
  • C
    cathode rays
  • x-rays
Answer
Correct option: D.
x-rays
D
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MCQ 71 Mark
Atomic number decreases with the emission of $\alpha-$-particles from the nucleus by :
  • A
    1
  • 2
  • C
    3
  • D
    4
Answer
Correct option: B.
2
B
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MCQ 81 Mark
The quantities that remain conserved in a nuclear reaction :
  • A
    Total charge
  • B
    Angular momentum
  • C
    Linear momentum
  • None of these
Answer
Correct option: D.
None of these
D
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MCQ 91 Mark
Time during which the amount of radioactive substance becomes half of its initial amount is called :
  • A
    Average life
  • Half life
  • C
    Decay constant
  • D
    Time period
Answer
Correct option: B.
Half life
B
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MCQ 101 Mark
Which one of following is charge less ?
  • A
    Alpha particle
  • B
    Beta particle
  • Photon particle
  • D
    Proton
Answer
Correct option: C.
Photon particle
C
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MCQ 121 Mark
Which one of the following has maximum penetrating power ?
  • A
    $\alpha$-rays
  • B
    $\beta$-rays
  • C
    Cathode rays
  • $\gamma$-rays
Answer
Correct option: D.
$\gamma$-rays
D
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MCQ 131 Mark
$\beta$-rays are deflected in :
  • A
    Gravitational field
  • B
    Only in magnetic field
  • C
    Only in electric field
  • Both in magnetic and electric fields
Answer
Correct option: D.
Both in magnetic and electric fields
D
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MCQ 151 Mark
The minimum energy of $\gamma$-photon to produce pair production will be :
  • A
    931 MeV
  • B
    9.31 MeV
  • C
    102 MeV
  • 1.02 MeV
Answer
Correct option: D.
1.02 MeV
D
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MCQ 171 Mark
In atomic bomb the source of large amount of energy is :
  • A
    Nuclear fusion
  • Nuclear fission
  • C
    Both (a) and (b)
  • D
    None of these
Answer
Correct option: B.
Nuclear fission
B
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MCQ 181 Mark
In hydrogen bomb large amount of energy is produced due to :
  • Nuclear fusion
  • B
    Nuclear fission
  • C
    Both (a) and (b)
  • D
    None of these
Answer
Correct option: A.
Nuclear fusion
A
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MCQ 191 Mark
Einstein's mass-energy relation is :
  • A
    $E = m c$
  • B
    $E =m c^2 / 2$
  • $E = m c ^2$
  • D
    $E = m / c$
Answer
Correct option: C.
$E = m c ^2$
C
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MCQ 201 Mark
Energy production in nuclear reactor is due to :
  • Nuclear fission
  • B
    Nucleus fusion
  • C
    Both (a) and (b)
  • D
    None of these
Answer
Correct option: A.
Nuclear fission
A
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MCQ 211 Mark
When two light nuclei are fused together to form a single heavy nucleus this process is called :
  • A
    Nuclear fission
  • Nuclear fusion
  • C
    Radioactivity
  • D
    None of these
Answer
Correct option: B.
Nuclear fusion
B
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MCQ 221 Mark
When a heavy nuclei breaks up into two equal nuclei, this process is called :
  • Nuclear fission
  • B
    Nuclear fusion
  • C
    Nuclear reaction
  • D
    None of these
Answer
Correct option: A.
Nuclear fission
A
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MCQ 231 Mark
The radioactive material does not emit :
  • A
    Electrons
  • Protons
  • C
    $\gamma$-rays
  • D
    Helium nuclei
Answer
Correct option: B.
Protons
B
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MCQ 241 Mark
The particle which is emitted from radioactive substance is :
  • Alpha
  • B
    Neutron
  • C
    Positron
  • D
    Proton
Answer
Correct option: A.
Alpha
A
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MCQ 251 Mark
In ${ }_0^1 n \rightarrow{ }_1^1 H +{ }_{-1}^0 \beta$ symbol ${ }_1^1 H$ represents :
  • A
    electron
  • proton
  • C
    $\gamma$-rays
  • D
    $\alpha$-particle
Answer
Correct option: B.
proton
B
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MCQ 261 Mark
Radioactivity is a phenomenon associated with :
  • Decay of nucleus
  • B
    Production of radio waves
  • C
    Transmission of radiowaves
  • D
    None of these
Answer
Correct option: A.
Decay of nucleus
A
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MCQ 271 Mark
Which of the following can be deflected by applying magnetic field ?
  • A
    $\alpha$-rays
  • B
    $\beta$-rays
  • C
    $\gamma$-rays
  • $\alpha-$ and $\beta$-rays both
Answer
Correct option: D.
$\alpha-$ and $\beta$-rays both
D
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MCQ 281 Mark
Which of the following has minimum wavelength ?
  • A
    yellow light
  • B
    X-rays
  • C
    $\alpha$-rays
  • $\gamma$-rays
Answer
Correct option: D.
$\gamma$-rays
D
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MCQ 291 Mark
Which of the following is electromagnetic wave ?
  • A
    $\alpha$-rays
  • B
    $\beta^{+}$-decay
  • C
    $\beta^{-}$-rays
  • $\gamma$-rays
Answer
Correct option: D.
$\gamma$-rays
D
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MCQ 301 Mark
In which disintegration out of the following disintegration atomic number decreases ?
  • A
    $\alpha$-decay
  • B
    $\beta^{+}$-decay
  • both (a) and (b)
  • D
    $\gamma$-decay
Answer
Correct option: C.
both (a) and (b)
C
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MCQ 311 Mark
In which of the following decay the structure of the nucleus does not change ?
  • A
    $\alpha$-decay
  • B
    $\beta^{+}$-decay
  • C
    $\beta^{-}$-decay
  • $\gamma$-decay
Answer
Correct option: D.
$\gamma$-decay
D
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MCQ 321 Mark
Out of radioactive radiation which has highest penetrating power ?
  • $\gamma$-rays
  • B
    $\beta$-rays
  • C
    $\alpha$-particle
  • D
    none of these
Answer
Correct option: A.
$\gamma$-rays
A
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MCQ 331 Mark
In radioactive disintegration $\alpha$-particle, $\beta$-particle and $\gamma$-rays are emitted. Out of these which has highest ionisation power ?
  • A
    $\gamma$-rays
  • B
    $\beta$-rays
  • $\alpha$-particle
  • D
    none of these
Answer
Correct option: C.
$\alpha$-particle
C
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MCQ 341 Mark
$\gamma$-rays are produced :
  • by nucleus of radioactive element
  • B
    by excited atom
  • C
    both (a) and (b)
  • D
    none of these
Answer
Correct option: A.
by nucleus of radioactive element
A
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MCQ 351 Mark
Number and type of nucleons in the nucleus of Deuterium $\left({ }_1^2 H \right)$ will be :
  • A
    2 protons
  • 1 proton and 1 neutron
  • C
    2 neutrons
  • D
    1 proton and 1 electron
Answer
Correct option: B.
1 proton and 1 neutron
B
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MCQ 361 Mark
Nuclear force is :
  • A
    gravitational force
  • exchange force
  • C
    magnetic force
  • D
    electrostatic force
Answer
Correct option: B.
exchange force
B
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MCQ 371 Mark
Atoms of an element differing in mass though possessing the same chemical properties are called :
  • A
    isotones
  • isotopes
  • C
    isobars
  • D
    isomers
Answer
Correct option: B.
isotopes
B
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MCQ 381 Mark
A $\beta$-particle is emitted from ${ }_{90}^{234} Th$ nucleus. The atomic mass number of the remaining nucleus A and atomic number Z for it will be respectively :
  • 234, 91
  • B
    234, 90
  • C
    230, 98
  • D
    232, 86
Answer
Correct option: A.
234, 91
A
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MCQ 391 Mark
The atomic number of two atoms are equal but their atomic masses are different. These will be
  • isotopes
  • B
    isobars
  • C
    isotones
  • D
    none of these
Answer
Correct option: A.
isotopes
A
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MCQ 401 Mark
The value of ratio N/Z is great for heavy nucleus because :
  • A
    neutron is heavy than proton
  • B
    neutron is a unstable particle
  • no any repulsive force is produced by neutrons
  • D
    range of coulombian force is equal to range of nuclear force
Answer
Correct option: C.
no any repulsive force is produced by neutrons
C
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MCQ 411 Mark
Which of the relations is correct for radioactive atom ?
  • A
    Half life = average life
  • B
    Half life = 2 × Average life
  • C
    Half-life = 1.6931 × Average life
  • Half-life = 0.6931 × Average life
Answer
Correct option: D.
Half-life = 0.6931 × Average life
D
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M.C.Q (1 Marks) - Physics STD 12 Science Questions - Vidyadip