Key Terms: Letter D

Daughter Nuclei

The stable or unstable nuclei that result from the decay of a parent nucleus in a nuclear reaction or radioactive decay process.

De Broglie Wavelength

The wavelength associated with a particle, calculated as the ratio of Planck’s constant to the particle’s momentum, demonstrating the wave-like nature of matter.

Density

The mass per unit volume of a substance, typically expressed in kilograms per cubic meter (kg/m³).

Detectors

Devices used to measure and record the presence, intensity, or characteristics of particles or electromagnetic radiation, such as light or sound.

Dielectric

An insulating material that increases the capacitance of a capacitor when placed between its plates, by reducing the electric field and allowing more charge to be stored.

Dielectric Constant

A measure of a material’s ability to resist the electric field and reduce the effective force between charges when placed in an electric field, compared to a vacuum.

Diffraction

The bending of waves around obstacles or through narrow openings, resulting in the spreading and interference of the wave.

Diffraction Grating

An optical device with closely spaced lines or slits that separates light into its component wavelengths through the phenomenon of diffraction.

Dipole Field

The electric field created by two equal and opposite charges separated by a distance, typically represented by two opposite poles of a dipole.

Direct Current

An electric current that flows in one constant direction, maintaining a consistent magnitude and polarity over time.

Discrete Emission Line Spectra

Patterns of specific wavelengths of light emitted by atoms or molecules when electrons transition between discrete energy levels, appearing as bright lines against a dark background.

Diverging Lenses

Concave lenses that spread parallel light rays apart, causing them to diverge as if originating from a single point called the focal point.