Done by: Chua Wei Hern (9) 2O1
p
rinciple of quantum physics holds that matter and
light exhibit the behaviors of both waves and particles,
depending upon the circumstances of the experiment.
O
ne of the most complex and confusing concept in
physics
BRIEF HISTORYA
ristotle was one of the first to publicly hypothesize about the nature of light, proposing
that light is a disturbance in the element air.
A
t the beginning of the 11th Century, the Arabic scientist Alhazen wrote the first
comprehensive treatise on optics; describing refraction, reflection, and the operation of a
pinhole lens via rays of light traveling from the point of emission to the eye.
B
eginning in 1670 and progressing over three decades, Isaac Newton developed and
championed his corpuscular hypothesis, arguing that the perfectly straight lines
of reflection demonstrated light's particle nature; only particles could travel in such
straight lines.
PHOTOELECTRIC EFFECT
T
he photoelectric effect refers to the emission or ejection of electrons from the surface
of generally a metal in response to incident light.
E
nergy contained within the incident light is absorbed by electrons within the metal,
giving the electrons sufficient energy to be emitted from the surface of the metal.
T
he more intense the incident light, the greater the energy with which the electrons
should be ejected from the metal.
O
ne of the experiments for wave-particle duality of light
A
way to prove light has particle properties.
PHOTONS
A
n elementary particle
B
asic unit of light
I
t is massless
H
as no electric charge
SOURCES
h
t
t
p
:
/
/
en.wikipedia.org/wiki/Photon
h
ttp://en.wikipedia.org/wiki/Wave
%E2%80%93particle_duality#Brief_history_of_wave_and_particle_viewpoi
nts
h
ttp://physics.about.com/od/lightoptics/a/waveparticle.htm
B
ooks
