Radiology Physics & Instruments - Intro to Physics

Protons, neutrons, and electrons.

Ionization involves the removal of an electron from an atom due to energy from radiation, which is crucial for creating X-rays.

Avogadro's number, $N_A = 6.022 × 10^{23}$ atoms/mol, is used to quantify the number of particles in one mole of a substance.

<p>Directly ionizing radiation interacts directly with atomic electrons, while indirectly ionizing radiation first interacts with other particles to produce secondary ionization.</p> Signup and view all the answers

<p>Ultraviolet, X-ray, and gamma ray.</p> Signup and view all the answers

<p>Electron rest mass is $0.511$ MeV/c² and proton rest mass is $938.3$ MeV/c².</p> Signup and view all the answers

<p>Electrons interact with radiation, which enables the generation of medical images through ionization processes.</p> Signup and view all the answers

<p>X-rays are emitted by orbital or accelerated electrons, while gamma rays are emitted by the nucleus or as a result of particle decay.</p> Signup and view all the answers

<p>Bremsstrahlung Radiation and Characteristic Radiation.</p> Signup and view all the answers

<p>Alpha particles have low penetration ability and can be stopped by a sheet of paper.</p> Signup and view all the answers

<p>It is produced when electrons slow down as they approach the nucleus, emitting energy in the form of X-rays.</p> Signup and view all the answers

<p>Gamma rays are highly penetrating and can pass through the body.</p> Signup and view all the answers

<p>Beta particles are smaller and can penetrate skin but are stopped by materials like plastic.</p> Signup and view all the answers

<p>Radioactive decay is used in nuclear medicine to trace radioactive substances in the body.</p> Signup and view all the answers

<p>X-rays are invisible and can penetrate soft tissue while being absorbed by bones.</p> Signup and view all the answers

<p>It is crucial for comprehending X-ray production processes and safe use of radiation in diagnostics.</p> Signup and view all the answers

<p>Characteristic X-rays are produced when an outer shell electron fills a vacancy left by an ionization or excitation process, emitting a photon whose energy is dependent on the difference in binding energies.</p> Signup and view all the answers

<p>Bremsstrahlung, meaning 'breaking radiation', occurs when charged particles lose kinetic energy due to interactions with other charged particles, converting it into electromagnetic radiation, essential for producing X-rays.</p> Signup and view all the answers

<p>Gamma rays are emitted when a daughter nucleus transitions to a more stable state following a nuclear reaction or spontaneous decay, releasing energy characteristic of the nuclear transition.</p> Signup and view all the answers

<p>During annihilation, a positron and an electron annihilate each other, producing two photons known as annihilation quanta, each with an energy of 0.511 MeV.</p> Signup and view all the answers

<p>Kerma stands for Kinetic Energy Released in Matter and measures the energy transferred to charged particles per unit mass in the absorber from indirectly ionizing radiation.</p> Signup and view all the answers

<p>Absorbed dose refers to the energy absorbed per unit mass of a medium, while equivalent dose accounts for the type of radiation, being the absorbed dose multiplied by a radiation weighting factor.</p> Signup and view all the answers

<p>Activity refers to the number of nuclear decays occurring per unit time, with its SI unit being the becquerel (Bq), which corresponds to one decay per second.</p> Signup and view all the answers

<p>Effective dose is the equivalent dose multiplied by a tissue weighting factor, reflecting the risk from different types of radiation exposure on human health.</p> Signup and view all the answers

<p>An Auger electron is emitted when energy transferred to an orbital electron during a transition results in a kinetic energy equal to the transition energy minus the binding energy.</p> Signup and view all the answers

<p>The photon energy in characteristic X-rays is unique to each atom and is determined by the difference in binding energies between the initial and final states of the electron transition.</p> Signup and view all the answers