Free Nuclear Physics MCQs with Answers
1,254 Nuclear Physics MCQs from Physics, each with the correct answer and a written explanation of why it is correct. Free and unlimited, with no account needed.
Atomic nuclei contain protons and neutrons, with nuclear size, mass defect and binding energy describing their stability. The work covers alpha, beta and gamma decay, decay equations, half-life and decay rate, along with radiation safety and medical applications such as imaging, radiotherapy and tracers.
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1,254 questions · page 16 of 63
- A. Strontium-90
- B. Carbon-14
- C. Iodine-131
- D. Cobalt-60
Explanation: Carbon-14 is a naturally occurring isotope used for radiocarbon dating of organic materials up to about 50,000 years old.
Correct answer: Carbon-14- A. Cannot be separated at all
- B. Have similar chemical properties
- C. Occur well separated in nature
- D. Cannot be separated by physical methods
Explanation: Isotopes of an element have the same number of protons and electrons, which primarily determines their chemical behavior.
Correct answer: Have similar chemical properties- A. 15 minutes
- B. 7.5 minutes
- C. 5 minutes
- D. 3.75 minutes
Explanation: If 7/8 has decayed, 1/8 remains. The fraction remaining is (1/2)ⁿ, where n is the number of half. lives. Since (1/2)³ = 1/8, three half.
Correct answer: 5 minutes304. An α. particle is emitted from ₈₈Ra²²⁶. What is the mass and atomic number of the daughter nucleus?
- A. 224, 84
- B. 220, 80
- C. 222, 86
- D. 226, 87
Explanation: Alpha decay involves the emission of an alpha particle (2He4), which consists of 2 protons and 2 neutrons.
Correct answer: 222, 86- A. Remains constant with time
- B. Decreases with time
- C. Increases with time
- D. May increase or decrease with time
Explanation: The rate of decay (activity) is directly proportional to the number of undecayed radioactive nuclei present.
Correct answer: Decreases with time- A. Remains the same
- B. Decreases
- C. Increases
- D. Equals to 1
Explanation: Beta decay involves a neutron converting into a proton (and an electron, which is emitted).
Correct answer: Increases- A. 9.315 MeV
- B. 931.5 MeV
- C. 93.45 MeV
- D. 1.025 MeV
Explanation: One atomic mass unit (u) is equivalent to a specific amount of energy, calculated using Einstein's mass.
Correct answer: 931.5 MeV- A. Temperature
- B. Nature of the element
- C. Pressure
- D. Amount of radioactive substance
Explanation: The half-life is an intrinsic property of a specific radioactive isotope, determined by the stability of its nucleus.
Correct answer: Nature of the element- A. 1820 years
- B. 1620 years
- C. 1940 years
- D. 1680 years
Explanation: The half-life of radium-226 (226Ra) is approximately 1620 years. It decays into radon-222 by emitting an alpha particle.
Correct answer: 1620 years- A. 12
- B. 36
- C. 33
- D. 39
Explanation: Xenon and Caesium are elements with a large number of known isotopes, both natural and artificially produced.
Correct answer: 36- A. Half the time it takes for the entire substance to decay
- B. Usually about 50 years
- C. The time for radium to change into lead
- D. The time for half the substance to decay
Explanation: Half-life is a fundamental concept in nuclear physics defined as the time required for one-half of the radioactive nuclei in a sample to…
Correct answer: The time for half the substance to decay- A. The number of undecayed nuclei present at that instant
- B. The time since the decay started
- C. The time remaining before all have decayed
- D. The half-life of the decay
Explanation: Radioactive decay is a first order process, meaning the rate of decay (activity) is directly proportional to the number of radioactive…
Correct answer: The number of undecayed nuclei present at that instant- A. 35
- B. 280
- C. 105
- D. 210
Explanation: The decay rate decreases in the same way as the number of nuclei. To decrease to one. fourth (1/2)² of the initial rate, two half.
Correct answer: 280- A. proton
- B. neutron
- C. electron
- D. photon
Explanation: A photon is a quantum of electromagnetic radiation, such as light. It has zero rest mass and zero electric charge.
Correct answer: photon- A. Photon energies
- B. The kinetic energies of the alpha particle and the daughter nucleus
- C. The excitation energy of the daughter nucleus
- D. The excitation energy of the alpha particle
Explanation: During alpha decay, the energy released (Q. value) is converted into the kinetic energy of the decay products.
Correct answer: The kinetic energies of the alpha particle and the daughter nucleus- A. Curved
- B. Zig Zag
- C. Straight
- D. Straggling
Explanation: An alpha particle is about 7000 times more massive than an electron. Due to its large mass and momentum, it is not easily deflected by…
Correct answer: Straight- A. 1590 x 10⁶ years
- B. 1590 x 10^25 years
- C. 1590 x 10¹² years
- D. Never
Explanation: Radioactive decay is an exponential process. In each half-life, only half of the remaining nuclei decay.
Correct answer: Never- A. α. rays
- B. γ. rays
- C. β. rays
- D. All have equal penetrating power
Explanation: Gamma (γ) rays are high. energy photons with no charge or mass, allowing them to penetrate matter much more deeply than charged particles…
Correct answer: γ. rays- A. Spontaneous decaying
- B. Self-disintegration property
- C. Chemical property
- D. Both A and B
Explanation: Radioactivity is the process by which an unstable atomic nucleus loses energy by emitting radiation.
Correct answer: Both A and B- A. Barium
- B. Hydrogen
- C. Lead
- D. Radium
Explanation: Many of the decay chains of heavy radioactive elements like Uranium and Thorium conclude with a stable isotope of lead.
Correct answer: Lead