Physics ยท Chemistry

Radioactivity and Nuclear Physics

519 Questions

Radioactivity and nuclear physics encompass the study of radioactive decay processes, neutron to proton ratios, and nuclear medicine. Questions cover various detection mechanisms, including scintillation counters and neutrino telescopes. These concepts are frequently tested in advanced science and civil services examinations.

Radioactive decayNuclear medicineParticle detectionNeutrino telescopesCosmic ray detection

Radioactivity and Nuclear Physics Questions

Multiple choice

A trace element

  1. is radioactive and can be traced by geiger-count

  2. is required in very minute amounts

  3. draws other elements out of protoplasm

  4. was one of the first to be discovered in protoplasm
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Trace element is an element that is required in minute quantities for physiological functioning.

Multiple choice

Of the following radiations, all are dangerous except

  1. cosmic rays

  2. short-radio waves

  3. ultra-violet rays

  4. X-rays
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Cosmic rays, UV rays, and X-rays are forms of ionizing or high-energy radiation that can damage biological tissues. Short-radio waves have much lower frequencies and energies, making them non-ionizing and generally safe for humans.

Multiple choice

Gamma rays have-

  1. Zero mass and no change

  2. Zero mass and positive change

  3. Unit mass and Zero change

  4. Unit mass and negative change
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Gamma rays are a form of high-energy electromagnetic radiation consisting of photons. Unlike alpha particles (positive charge) or beta particles (negative charge), gamma rays have no rest mass and carry no electrical charge. This lack of charge and mass allows them to have high penetrating power through matter.

Multiple choice

Which of the following statements is/are false? (P) Manganese is used as scavenger in making steel. (Q) All known isotopes of technetium are radioactive, except 98Tc. (R) Rhenium is used in making electric furnace windings and spectrophotometer filaments.

  1. P only

  2. Q only

  3. P and Q

  4. Q and R

  5. All of these
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

(P) Manganese is an important additive in steel making and acts as a scavenger as it has the property of removing both oxygen and S and thus preventing bubbles and brittleness. (Q) Technetium (99Tc) was the first man-made element with radioactive property. All known isotopes of technetium (includes 97Tc, 98Tc) have radioactive property. It is one of the fission products of uranium. It obtained by spent fuel rods in nuclear reactors. (R) Rhenium is used in making electric furnace windings and spectrophotometer filaments due to its very high melting point (3180oC).

Multiple choice

Which of the following rays have the highest energy?

  1. Alpha rays

  2. Beta Rays

  3. Gamma Rays

  4. X- Rays
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Gamma rays have the highest frequency in the electronic spectrum of radiations. Hence, as per plank's equation: E = hv, where h is plank's constant and v is the frequency, they have the highest energy.

Multiple choice

Which one of the following statements is not true?

  1. Nuclear disintegration does not involve any external means

  2. It results in emission of powerful radiation.

  3. It is dependent on the number of electrons present in the outer shell of an atom.

  4. It shows photographic effect.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

It is a nuclear phenomenon and hence independent of the number of electrons present in the outer shell of atom.

Multiple choice

What is the reason for 27Co60 radioactivity?

  1. Its atomic number is high.

  2. It has high P/N ratio.

  3. It has high N/P ratio.

  4. None of these
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

It is the N/P ratio which affects the radioactivity of a substance. The higher the N/P ratio, more unstable will be the nuclide.