Wavesssss Flashcards
What is a wave
A disturbance or oscillation that travels through space and matter, accompanied by a transfer of energy
What are the two types of wave classification based on medium
Mechanical wave that requries medium for propagation
Electromagnetic wave that is able to propgate thr a vacuum
What are the two type of waves classification based on direction
Transverse wave
- components vibrate perpendicular to direction of propagation
Longtitudinal
- components vibrate parallel to direction of propagation
What is frequency (f)
No. of cycles of a wave that pass a reference point in certain period of time
What is wavelength (λ)
Distance between peaks/ trough
What is period (T)
duration of one cycle in a repeating event
What is the relationship between period and frequency
T = 1/f
What is velocity
Rate of travel or distance wave travel in certain period of time
What is the velocity of EM waves in vacuum
3 x 10^8 m/s =
How to calculate velocity with frequence and wavelength
v = fλ
What is visible light
The portion of EM spectrum that stimulates the human visual system
What is electromagnetic wave
Waves that can travel through the vacuum
What is electromagnetic spectrum
Distribution of electromagnetic radiation according to energy/ frequency/ wavelength
What are some characteristics of EM waves
EM energy travels as transverse wave
Constant speed in vacuum at 3 x 10^8 m/s
Requries no medium to propagate
Consists of varying electric and magnetic field
- vibrate perpendicular to each other and to direction of travel
- vibrate at same freq. of the wave
Unaffected by electric and magnetic field
Trave in straight line within set limit by diffraction
Capable to being polarized
Quantity of energy carried by EM waves depends on magnitiude of distrubance in electric and magnetic field
Cna be caused to produce interference effects
Name the different spectrums in the Electromagnetic spectrum
Highest wavelength, lowest freq.)
Radio
Microwaves
Infrared
Visual spectrum (red to blue)
Ultraviolet radiation
X-rays
Gamma rays
What is a source
Any object that emits EM radiation
What are the two types of sources
Point source
- source either infinitely small or sufficiently far away
Extended source
- A source with measurable area
What are the two choromatic type of sources
Monochromatic source
- emits em radiation of single wavelength or freq
Polychromatic source
- emits em radiation of several wavelength or freq.
What is a wavefront
Arc/ curve formed with ctr at source by connecting same posiston on all waves
What is teh law of malus
Rays are perpendicular to wavefronts
Pinhole formula
h/h’ = a/a’
’ always at btm (the one behind the barrier)
What is depth of field
Distance object can move without affecting sharpness of image in specific fixed position
What is depth of focus
Distance image screej can move while mainting a sharp img for fixed obj. position
What is a shadow
Region which a given type of radiation would not reach due to the presence of an obj.
What is the shadow of a extended light source
Umbra n penumbra
What is the shadow of a point source
Geometric shadow with sharp edge
What is the region of illumination for a point source when shone thr a aperture
Full illumination (uniform light on screen)
What is the region of illumination for a extented source when shoen thorugh a aperture
Centeral rull illumination, outer annules of partial ilumination
