L10(a) Interaction of light with matter Flashcards
1
Q
3 ways light interact with matter
A
RAT
- when light strikes a substance, some absorption and reflection always happens
- no substance completely R/A/Ts all of the light rays that reach its surface
2
Q
explain transmission
A
- where light passes through an object without being essentially charged (eg. passes through object)
- substance transmit almost all light =transparent
3
Q
explain absorption
A
- when only part of light is transmitted, the rest absorbed (eg. energy retained in object)
- substance that do not transmit any light=opaque
- opaque: either absorb or reflect
4
Q
explain reflection
A
- when light fully/partially (diffused) reflected (eg. energy bend back)
- substance allow some rays to pass but object not seen clearly as rays diffused= translucent
5
Q
factors determining light perceived as colour by our eyes
A
- wavelength/frequency of incident light
- characteristics of object
determines % of RAT
6
Q
explain factor of wavelength/frequencies of incident light
A
- sunlight, visible part of EM spectrum -> perceived as white
- diff colour components varying with wavelengths and frequency
7
Q
explain factor characteristics of object
A
- transparent - most light transmitted
- translucent - transmitted light diffused
- opaque - most light absorbed
a. smooth - speculation reflection
b. rough - diffuse reflection
c. glossy
8
Q
explain colour perception of objects (opaque/translucent)
A
- colour of object perceived is the colour component of the light that is NOT absorbed by the object
- an opaque object appears a certain colour by absorbing all wvl except those wvl corresponding to that particular colour perceived
- waves reflected from opaque object strike your eye causing you to see that particular colour
-a translucent object appears that certain colour by absorbing all wvl except those wvl correspond to that particular transmitted by translucent object
