Atomic and Nuclear Physics Overview

These flashcards capture the key concepts and principles from atomic and nuclear physics, as outlined in the lecture notes.

What is black body radiation?

An object which absorbs all radiation falling upon it and does not reflect any.

What does Wien's displacement law describe?

It describes how the peak wavelength emitted by a black body is inversely proportional to its absolute temperature.

What is Stefan's Law in relation to blackbody radiation?

The rate at which an object radiates energy is proportional to the fourth power of its absolute temperature.

What is Rayleigh-Jean's Law?

An early classical attempt to explain blackbody radiation that matched experimental results at long wavelengths.

Who developed a theory of blackbody radiation in 1900?

Max Planck.

What is Planck’s hypothesis regarding energy absorption or emission?

An object can only gain or lose energy in discrete packets called quanta.

What does an energy-level diagram illustrate?

It shows the quantized energy levels and allowed transitions of an atom.

What is fluorescence in molecular absorption?

The absorption of light at a higher frequency followed by the emission of light at a lower frequency.

What does atomic spectroscopy analyze?

The composition of unknown materials, monitoring air pollutants, and studying atmospheres.

What is a laser and how is it produced?

A laser is produced through stimulated emission of photons that are identical and coherent.

What is the photoelectric effect?

The phenomenon where light strikes a metal surface causing the ejection of electrons.

What is the work function in the context of the photoelectric effect?

The minimum energy required to liberate an electron from a metal.

What is the significance of the cutoff frequency in the photoelectric effect?

It is the minimum frequency of incident light needed to eject electrons from the metal surface.

What is the strong nuclear force?

The force that holds nucleons together in the nucleus, stronger than the electrostatic force at short ranges.

What are isotopes?

Atoms with the same number of protons but different numbers of neutrons.

What is radioactive decay?

The process by which unstable nuclei lose energy by emitting radiation.

Define half-life in nuclear physics.

The time required for half of the radioactive nuclei in a sample to decay.

What is meant by binding energy?

The energy required to disassemble a nucleus into its constituent protons and neutrons.

What is a beta particle?

An electron emitted from a nucleus during the decay of a neutron.

What is the difference between ionization energy and binding energy?

Ionization energy is needed to remove an electron from an atom, while binding energy is needed to disassemble a nucleus.

What is the significance of Bohr's model of the atom?

It introduced the concept of quantized energy levels for electrons in an atom.