Physics
Definitions
|
| Declination
(θ) : Declination at a place is the angle between
the geographic meridian and the magnetic meridian at the place.
It is denoted by θ. |
|
| Dielectric
Strength : The maximum value of electric field intensity
(i.e. potential gradient) that can be applied to a dielectric
without its electric breakdown is called dielectric strength
of the dielectric. |
|
| Diamagnetic
Substance : Those substances which when placed in a magnetic
field are weakly magnetized in a direction opposite to that
of the applied field are called diamagnetic substances. e.g. bismuth, copper, zinc, gold, water
etc. |
|
|
Diffraction
: If light waves pass over an obstacle or pass through
a narrow opening, they end partially at the edges of the obstacle
or the opening. This spreading of light waves that pass through
a narrow opening or move past an obstacle is called diffraction. |
|
| Doppler
Effect : The apparent change of frequency and wavelength of a source of wave when there is a relative motion between the source and the observer is called
Doppler effect. |
|
| Digital
Signal : A signal (voltage or current) that can have only
two discrete values is called a digital signal. |
|
| Digital
Circuit : An electronic circuit that handles only a digital
signal is called a digital circuit. |
|
| Demodulation
or Detection : The process of recovering the audio signal
from the modulated wave is known as demodulation or detection. |
