Radioactivity and particles：练习题

An atom of a radioactive isotope has 92 protons and 143 neutrons. What is its mass (nucleon) number?

Which statement correctly describes the initiation of nuclear fission in a Uranium-235 nucleus?

A laboratory technician accidentally gets radioactive dust on their skin while handling a faulty container. They later undergo a routine check-up involving exposure to high-energy X-rays.
Which option correctly identifies the types of exposure received by the technician in each scenario?

What type of ionising radiation is the most penetrating?

A sample of a radioactive isotope has an initial activity of 400 Bq. After 6 hours, its activity has dropped to 50 Bq. What is the half-life of this isotope?

Describe the nature of a beta particle (\(\beta^-\)) and state its relative penetrating power compared to alpha particles and gamma rays.

Explain the key difference between contamination and irradiation when dealing with exposure to radioactive sources.

Describe the specific interaction that initiates the process of nuclear fission in a Uranium-235 nucleus and state the immediate products of this reaction.

The nucleus of a Uranium atom can be represented using the symbol \({}^{238}_{92}\mathrm{U}\).

(a) State the number of protons and the number of neutrons present in a \({}^{238}_{92}\mathrm{U}\) nucleus.

(b) Alpha (\(\alpha\)) particles, beta (\(\beta^-\)) particles, and gamma (\(\gamma\)) rays are three types of ionising radiation. Which of these three is an electromagnetic wave?

Alpha (\(\alpha\)) particles, beta (\(\beta^-\)) particles, and gamma (\(\gamma\)) rays have different properties, including penetrating power and ionising ability.

(a) Describe the structure and relative charge of an alpha particle and a beta particle.

(b) Explain why gamma radiation is commonly used to sterilise surgical equipment, whereas alpha radiation is unsuitable for this purpose. Relate your answer to penetrating power.

(c) Compare the ionising ability of alpha particles and gamma rays over a short distance in the air.