Exam 3 Review: Periodic Motion, Waves, Light, Radioactivity

These flashcards cover key concepts related to periodic motion, waves, light, and radioactivity as discussed in preparation for Exam 3.

Index of Refraction

A measure of how much light slows down in a medium compared to a vacuum.

Snell's Law

Describes the relationship between the angles of incidence and refraction when light passes through different media: n1sin(θ1) = n2sin(θ2).

Critical Angle

The angle of incidence above which total internal reflection occurs.

Alpha Decay

A type of radioactive decay where an alpha particle (4He nucleus) is emitted from the nucleus.

Beta Decay

A radioactive decay process where a neutron transforms into a proton or vice versa, emitting an electron or positron.

Radioactivity

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

Half-Life

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

Binding Energy

The energy required to separate nucleons from the nucleus, representing a difference in mass.

Nucleons

Particles in the nucleus, including protons and neutrons.

Activity (R)

The number of decay events per unit time, expressed in becquerels (Bq).

Gamma Decay

A type of radioactive decay involving the emission of gamma rays, resulting in no change in the number of nucleons.

Carbon-14 Decay

A process by which carbon-14 transforms into nitrogen-14 through beta decay.

Proton Number (Z)

The number of protons in an atom's nucleus, determining the element's identity.

Decay Constant (λ)

A constant that represents the probability of decay of a radioactive substance; units are typically in s^-1.

Excited State

A state of a nucleus after decay where it can release energy as a photon.

Isotope

Atoms of the same element with different numbers of neutrons.

Activity Calculation Formula

R = λN, where R is activity, λ is decay constant, and N is the number of atoms.

Total Internal Reflection

The complete reflection of light within a medium when it hits the boundary at an angle greater than the critical angle.

Fission

The process where a heavy nucleus splits into lighter nuclei, releasing energy.

Fusion

The process where two lighter nuclei combine to form a heavier nucleus, releasing energy.

Coulomb's Repulsion

The electrostatic repulsive force between positively charged protons.

Radiation

Particles or electromagnetic waves emitted from unstable nuclei, including alpha, beta, and gamma radiation.