Speed of light
This scientist unified electricity and magnetism, laying the foundation for understanding electromagnetic waves.
Maxwell
the wave equation
v=fλ
This effect, where electrons are emitted from a metal surface when light shines on it, cannot be explained by the wave model alone
The photoelectric effect
Einstein's first postulate of special relativity states that the laws of physics are the same in all of these types of reference frames.
inertial (or non-accelerating) reference frames
In the equation E=mc2, the 'c' represents this universal constant.
the speed of light in a vacuum
The speed of all electromagnetic waves in a vacuum is approximately this value
What is 3×108 m/s (or the speed of light)?
Lasers produce light that is monochromatic, coherent, and highly directional. What does "monochromatic" mean?
light of a single wavelength (or a very narrow range of wavelengths/colors)
This type of idealized object absorbs all incident electromagnetic radiation and emits radiation solely based on its temperature
black body
Ampere / Faraday
The bright and dark patterns observed when light from two sources overlaps are evidence of this wave property
interference
The minimum frequency of light required to cause the photoelectric effect in a particular metal is known as this
Threshold Frequency
The name of the factor that calculates special relativity
Lorentz Factor
When a small amount of mass is destroyed in a nuclear reaction, a very large amount of this is released.
energy (or nuclear energy)
These electromagnetic waves have the longest wavelengths and are used in broadcasting and communication.
What are radio waves?
This phenomenon describes the splitting of white light into its constituent colors when it passes through a prism.
dispersion
Wien's Law relates the peak wavelength of radiation emitted by a black body to this physical property of the object.
its temperature
Who's observations confirmed Maxwell's predictions?
Heinrich Hertz
Before Maxwell, these two historical and contemporary methods were used to determine the speed of light
astronomical observations (e.g., Römer's observations of Jupiter's moons) and terrestrial measurements (e.g., Fizeau's toothed wheel or Foucault's rotating mirror)
In the photoelectric effect, the maximum kinetic energy of the emitted photoelectrons depends on this property of the incident light, not its intensity.
the frequency (or energy) of the incident light
This phenomenon describes the observation that a moving clock runs slower than an identical stationary clock.
time dilation
Explain how the total mass of the products in a nuclear fission or fusion reaction compares to the total mass of the reactants, and what happens to the 'missing' mass.
The total mass of the products is slightly less than the total mass of the reactants, and the "missing" mass has been converted into energy
This portion of the electromagnetic spectrum is responsible for sunburns and can be harmful in excessive amounts.
What is ultraviolet (UV) light?
Optical fibres transmit information using this principle, where light reflects internally within the fibre due to a difference in refractive indices.
total internal reflection
Max Planck's contribution to understanding black body radiation involved proposing that energy is emitted in discrete packets called these.
quanta (or photons)
Transmitter and spark gap
The speed of electromagnetic waves can be predicted using these two fundamental constants
permeability of free space
permittivity of free space
This constant, with a value of approximately 6.626×10−34 J s, relates the energy of a photon to its frequency
Planck's constant
According to special relativity, the length of an object measured by an observer in relative motion will appear to do this compared to its proper length.
contract
If an object gains a significant amount of kinetic energy, its relativistic mass will subtly do this, illustrating the mass-energy equivalence.
increase
Medical imaging techniques like CT scans utilize these high-energy electromagnetic waves.
What are X-rays?
Explain how the photoelectric effect is utilized in a device such as a solar cell or a photodiode to generate an electric current.
When photons of sufficient energy (above the work function) strike a semiconductor material, they eject electrons, creating a flow of charge (current) in the circuit
This phenomenon, where the oscillations of a wave are restricted to a single plane, provides evidence for the transverse nature of light.
polarization
Scientists that measured the speed of light
Rosa and Dorsey
Who first developed the wave equation?
Hertz
If the frequency of incident light is below the threshold frequency, increasing the intensity of the light will have this effect on photoelectron emission.
no effect (or no photoelectrons will be emitted)
This famous equation, E=mc2, expresses the equivalence between what two fundamental physical quantities?
mass and energy
The mass defect in atomic nuclei, which is the difference between the mass of a nucleus and the sum of the masses of its individual nucleons, can be directly converted into this form of energy.
Binding Energy
Arrange the following in order of increasing wavelength: visible light, microwaves, gamma rays, infrared.
What is gamma rays, visible light, infrared, microwaves? (Or gamma rays→visible light→infrared→microwaves)
The equation dsinθ=mλ is used to quantitatively analyze interference patterns from this optical component.
diffraction grating
The Law of Malus, I=Imaxcos2θ, quantitatively describes the intensity of plane polarized light after passing through what?
a second polarizer (or an analyser)