The Wave Nature of Light Flashcards
How is the wave nature of light demonstrated?
Young’s double slit experiment, which shows light undergoes diffraction and interference
What is a diffraction grating?
It is made of transparent material with precision engraved parallel lines that block the light
What is a grating constant?
The difference between adjacent slits
How can polarisation of light be used to our advantage?
Reflection polarisation
Reducing bright light
Polaroid lenses (optical equipment)
Stress testing (in plastic)
What is dispersion?
The separation of light into its constituent colours
What effects do prisms have on light?
Prisms disperse light, blue bends the most and red the least
What effects do gratings have on light?
A grating diffracts light, red diffracts the most and blue the least
What is recombination?
The opposite of dispersion, the three primary colours are mixed to make white light
What are primary colours?
The three colours that combine to make white light, red blue green
What is a secondary colour?
A colour resulting in two primary colours being mixed in equal parts, cyan yellow magenta
What are complementary colours?
Primary and secondary colours that combine to make white light
Explain infrared (IR) rays.
-All hot objects emit infrared
-IR can be used to take thermograms which are heat images
-Useful for detecting objects in mist or darkness
-Remotes use IR to send signals
Explain ultraviolet rays.
-UV causes sunburn and tan
-Can cause cancer
-Helps production of vitamin D
-Can be used for photoelectric effects
-Causes fluorescence in some objects
-Cannot pass through ordinary glass
