Light Flashcards
Photon energy corresponds with what energy difference?
Photon energy corresponds with the energy difference between electron orbitals
Photon absorption vs photon emission
Absorption: Absorbing a photon causes an electron to jump energy levels
Emission: An electron emits a photon when it drops energy levels
Mnemonic: AHED
Absorption; Higher potential; Emission; Decreased potential
Photons
Photoelectric effect
The effect of electrons being ejected from light striking a metal.
Photons
Planck’s equation and constant value
ΔE=hf
h = Planck’s constant = 6.626 x 10-34 J s
Used to find the energy of a photon of light, which corresponds with the change in energy of electron orbital levels
Photons
Fluorescence
Occurs when light causes an electron to jump to a higher energy state. Next, the electron returns to its original energy level and emits a photon.
The emitted photon has lower energy and greater wavelength.
Polarized light has its oscillations and electromagnetic fields in a particular orientation.
Can be achieved by passing light through a polarizing filter.
What is plane polarization?
Plane polarized light has waves that all oscillate in the same plane or axis.
Polarized light has its oscillations and electromagnetic fields in a particular orientation.
Can be achieved by passing light through a polarizing filter.
What is circular polarization?
Circularly polarized light consists of electric fields of equal intensity that constantly rotate in direction.
Light interactions
Interference
Interactions of waves.
Seen in the Young’s double slit experiment of waves, which produces alternating dark spots due to destructive interference and bright spots due to constructive interference.
Light interactions
Diffraction
The bending or spreading out of light as it passes through a slit or opening.
Diffraction is most significant when the opening is smaller than the wavelength of the light.
Light interactions
Diffraction grating equation
An experimental setup with a series of slits that diffract light into its component colors.
dsin(θ)=mλ
θ = angle of separation
d = distance between slits
λ = wavelength
m = position of slit
Light interactions
Refraction
n= c/v
n = index
c = speed of light in vacuum
v = speed of light in given medium
Refers to the change in angle and speed of light as it changes mediums.
Light interactions
Snell’s Law
The index of refraction (n) is inversely proportional to the sine of the angle of refraction (θ).
n1 sin(θ1) = n2 sin(θ2)
The index of refraction for air is approximately equal to 1
Electromagnetic spectrum
Electromagnetic waves:
Transverse waves that consist of two perpendicular, oscillating fields. One is an electric field and one is a magnetic field.
Both of the fields are perpendicular to the direction of the wave.
