AtomicTheory
History of AtomicTheory
Theevidence behindthebuild up of the currenttheoryof atomic structure
1 high is a wave
2 energy of light is proportional to its frequency
3 Light is also a particle
4 Atomshave discrete emission spectra
5 electron orbits are quantized
1690i WaveTheory of light
treatlightmathematically as waves
problem waves propagate through a medium
solution the luminiferous aether createdmedium forlighttotravelthrough
Wave Nature of Light
Frequency V no J
of waves passing a givenpoint per second
t
units s Hz
Wavelength 2 lambda
distance btwn 2 successive crests troughs
Unit nm or ftm
3.00 108 8.00 1014 y
Speed c VX
distancetravelled
per unit time 2.998 108 m s
, 1900 iBlackbody radiation
the colour of light emitted 2 depends on temperature of object
observed spectra couldnotbe fitted with classical physics
Planck Energy is quantized i
Energy of radiation is proportional to its frequency
AE hV
h Planck'sconstant 6.6262 1034 Jls
Back to wave theory
is E heyzhu
Light w long z Ismailv has a small E
lshort larger Large
Lightbehaves like a wave butits energy is quantized
1905 Photoelectric effect
Einstien experimental observations makesense if lightconsists of particles called photons of
discreteenergy
I Light is both a wave s a particle
1752i Atomic Spectra
Light of differentcolours is produced when elements are eithersubmitted to an electric
discharge or are placed in a flame
History of AtomicTheory
Theevidence behindthebuild up of the currenttheoryof atomic structure
1 high is a wave
2 energy of light is proportional to its frequency
3 Light is also a particle
4 Atomshave discrete emission spectra
5 electron orbits are quantized
1690i WaveTheory of light
treatlightmathematically as waves
problem waves propagate through a medium
solution the luminiferous aether createdmedium forlighttotravelthrough
Wave Nature of Light
Frequency V no J
of waves passing a givenpoint per second
t
units s Hz
Wavelength 2 lambda
distance btwn 2 successive crests troughs
Unit nm or ftm
3.00 108 8.00 1014 y
Speed c VX
distancetravelled
per unit time 2.998 108 m s
, 1900 iBlackbody radiation
the colour of light emitted 2 depends on temperature of object
observed spectra couldnotbe fitted with classical physics
Planck Energy is quantized i
Energy of radiation is proportional to its frequency
AE hV
h Planck'sconstant 6.6262 1034 Jls
Back to wave theory
is E heyzhu
Light w long z Ismailv has a small E
lshort larger Large
Lightbehaves like a wave butits energy is quantized
1905 Photoelectric effect
Einstien experimental observations makesense if lightconsists of particles called photons of
discreteenergy
I Light is both a wave s a particle
1752i Atomic Spectra
Light of differentcolours is produced when elements are eithersubmitted to an electric
discharge or are placed in a flame
