3) Waves Flashcards
Define Wave motion:
Wave motion is the transfer of energy from one place to another, without transferring matter.
Define Wavefront:
Wavefront is the imaginary line joining all the crests on a wave.
Define Wavelength:
Wavelength is the distance between two consecutive crests, two consecutive troughs or between any two points in phase.
Define Frequency
Frequency is defined as the number of vibrations passing trough a point per unit time.
Define Transverse wave
A transverse wave ia a wave in which the direction of vibration is at right angles to the direction of propagation . Examples include: electromagnetic radiation, water waves and seismic S-waves (secondary) can be modelled as transverse.
Define Longitudinal wave:
For a longitudinal wave, the direction of vibration is parallel to the direction of propagation . Examples include: sound waves and seismic P-waves (primary) .
Define Refraction
It is the bending of light when light changes media.
Define Reflection:
It is the bouncing back of waves after hitting a surface.
Define Diffraction:
Diffraction is the spreading of waves around obstacles.
Define Angle of incidence:
It is the angle between the incident ray and the normal.
Define Angle of refection:
It is the angle between the reflected ray and the normal.
Define Normal
A normal is a perpendicular line drawn to a surface , at the exact point where the incident ray hits the surface
Define Plane mirror:
A plane mirror is a mirror with a flat reflecting surface.
Define Critical angle:
Critical angle is that angle of incidence , for which the angle of refraction is 900.
Define optical fibre:
An optical fibre is a fibre that is made of silica or plastic , with a diameter just slightly greater than a human hair. It is by nature flexible and transparent .
