Every point on a wave front can be considered as a source of tiny wavelets that spread out in the forward direction at the speed of the wave itself.
In particle theory, Newton thought light traveled as a shower of particles each proceeding in a straight line.
606 - 668 THz.
Diffraction.
Diffraction and interference.
The speed of light is slower in water than in air.
Wave-particle duality postulates that all particles exhibit both particle and wave properties.
Electromagnetic spectrum.
Reflection, shadows, and light traveling in straight lines.
The wavelength and speed.
When the gap size is approximately the same or smaller than the wavelength of the light wave.
Both wave theory and particle theory do not provide the full picture of the nature of light.
Light from a source arrives on a mirror surface as a stream of particles that will bounce away from the smooth surface.
Laws of reflection and refraction.
Because people can usually hear sound from behind an obstacle, but we do not see light, indicating that light shows no diffraction.
In particle theory, Newton thought light traveled as a shower of particles each proceeding in a straight line.
Particles accelerate as they go from air to a medium of greater optical density.
Monochromatic (single wavelength) light.
Wave-particle duality, Young’s double-slit experiment, Electromagnetic spectrum, Laws of reflection and refraction, Diffraction and interference.
Rectilinear propagation of light is the concept that light travels in straight lines.
θ1 > θ2
The particle theory.
Thomas Young.
When two waves combine to form a resultant wave with reduced or zero amplitude.
A series of bright fringes.
Destructive interference.
Waves start out from the slits in phase (crest to crest) and may arrive in phase at the screen if the paths differ by a whole wavelength, causing constructive interference. They may also end up out of phase (crest to trough) if the paths differ by half a wavelength, causing destructive interference.
A bright fringe appears on the screen.
It states that all particles have a wave nature and vice versa.
Its direction of propagation changes.
Near-infrared light is closest in wavelength to visible light and is usually used in TV remote-controls.
It bends away from the normal.
Young's double-slit experiment.
Isaac Newton.
How could waves travel in straight lines?
The light speed in water is faster than that in air.
The particle theory can explain light reflection, refraction, and rectilinear propagation.
More and more experiments, including Young's double-slit experiment.
Constructive interference occurs.
Young's double-slit experiment.
It occurs where the waves are crest to crest or trough to trough.
They depict the simulation results, showing regions of constructive and destructive interference moving out from the slits at well-defined angles to the original beam.
The rectilinear propagation of light strongly supports particle theory.
Refraction of light is the bending of light when it travels obliquely from one transparent medium into another.
Wave-particle duality.
The refractive index (n) is calculated as the ratio of the velocity of light in vacuum (c) to the velocity of light in the medium (v), n = c/v.
Electromagnetic spectrum
The angle of refraction is the angle between the refracted ray and the normal.
High frequency waves.
Gamma ray, X-ray, Ultraviolet (UV) light, Visible light, Infrared (IR) light, Radio wave.
When light passes from a dense material into a less dense material and refracts away from the normal.
Wave-particle duality.
Opticks, published in 1704.
The beam spreads and becomes wider than expected, supporting wave theory.
Reflection, refraction, and rectilinear propagation.
Sir Isaac Newton.
Young's double-slit experiment.
Because different numbers of wavelengths fit into each path.
He first passed light from a single source (the sun) through a single slit.
Dark fringes (or dark spots) are observed.
Laws of reflection and refraction.
The wave-particle duality.
Light travels in a straight line.
Mid-infrared light is usually used in environmental gas monitoring and breath analysis.
They shone laser light through two slits in a barrier made of a material that blocked light.
A photon.
The angle of incidence is equal to the angle of reflection.
The angle of refraction increases.
The pinpoints of light accumulated in bands that resembled interfering waves.
Light travels 1.33 times as fast in a vacuum than it does in water.
A smooth and shiny surface.
186,000 miles per second.
General illumination.
By dividing the speed of light in a vacuum by the speed of light in water (186,000 miles/second ÷ 140,000 miles/second = 1.33).
A half-integral multiple of the wavelength, i.e., d sin θ = (m + 1/2)λ, where m = 0, ±1, ±2, ...
Because they exhibit very small wavelengths.
It effectively becomes a secondary source of the propagating wave.
He was the first to record accurate observations of the phenomenon of diffraction.
The light spreads out horizontally on either side of the incident beam into a pattern called interference fringes.
484 - 508 THz.
Both diffraction and interference are about waves and show how waves can bend, spread out, or overlap.
The new wave front is the envelope of all the wavelets and tangent to all of them.
Some light refracts and some reflects, which are characteristics of waves.
As small compact particles of energy called corpuscles, flying through a void.
In particle theory, Newton thought light traveled as a shower of particles each proceeding in a straight line.
Christian Huygens.
They bounce from different points, reversing their order and producing a reversed image.
Light is never known to follow crooked passages nor to bend into the shadow, and it must always travel in straight lines.
A force pulls particles into the media.
The electromagnetic spectrum is the range of all types of electromagnetic radiation, from radio waves to gamma rays.
The laws of reflection state that the angle of incidence equals the angle of reflection. The laws of refraction, described by Snell's law, relate the angles of incidence and refraction to the indices of refraction of the two media.
The wave nature of light.
Only two slits appearing on the screen.
The wave nature of light through interference patterns.
Two coherent light sources that then interfere constructively or destructively.
Electromagnetic spectrum.
It occurs where the waves are crest to trough.
They depend on the wavelength and the distance between the slits.
Max Planck, Albert Einstein, Niels Bohr, and many others.
Refraction.
The symbol 'n' is usually used to represent the refractive index.
n = (velocity of light in a vacuum) / (velocity of light in medium).
Far-infrared light causes the warmth people feel when basking in the sun and is used in food-heating lamps.
The angle of incidence is the angle between the incident ray and the normal.
n1 * sin(θi) = n2 * sin(θr)
Energy emitted in the form of a wave because of the motion of electric charges.
Laws of reflection and refraction.
a) Young’s double-slit experimental results can be used as the evidence to support wave theory b) In Young’s experiment, he observed a series of bright fringes on the screen c) In Young’s experiment, the closer the slits are, the more is the spreading of the bright fringes
Reflection, refraction, and rectilinear propagation of light.
It is explained by forces acting on boundaries between different media.
Young’s double-slit experiment demonstrates the wave nature of light through the interference pattern created when light passes through two closely spaced slits.
Because it can explain how particles bounce off a smooth surface and produce a reversed image.
Light particles are in a state of equilibrium before and after entering water.
Constructive interference.
Destructive interference occurs when waves from the slits arrive out of phase (crest to trough) at the screen, with their paths differing by half a wavelength.
The light must fall on a screen and be scattered into our eyes.
The refractive index is a measure of how much light slows down when it goes into a new medium.
It bends towards the normal.
0.0100 mm
Ultraviolet waves have frequencies slightly higher than visible light.
The refracted ray follows a path exactly along the surface of the dense medium.
When light reflects a smooth and shiny surface, it gets reflected in the same medium forming an image of the object.
Ultraviolet light is used to disinfect surgical equipment and is necessary for humans to produce vitamin D.
The light is no longer refracted and is instead reflected inside the medium.
Ultraviolet light causes sunburn by penetrating the top layer of skin.
Only thick layers of lead or concrete.
They cause burns, mutations, and damage to growing tissues.
Our sun (and other stars) nuclear fusion reactions.
As a discrete 'packet' of energy.
Radio wave.
A narrow slit or the corners of an obstacle.
668 - 789 THz.
508 - 526 THz.
Yes, diffraction can occur when waves curve around an edge.
The amplitudes of the two waves are added, but since they are in opposite phase, they cancel each other out.
Both diffraction and interference produce spatial patterns like fringes or bands of light and dark areas.
60°
Because n1 * sin(θi) / n2 = 1.3, which is greater than 1.
The light speed in water must be faster than that in air.
Sunlight.
The Sun.
The light waves are in phase or have a definite phase relationship.
b) Wave theory presents advantages in explaining light diffraction.
No, radio waves have different frequencies.
Wave-particle duality
X-rays pass through skin and muscle but are reflected by teeth and bones.
A special camera that was very sensitive to light.
Electromagnetic spectrum.
Using the formula λ = (d * sin(θ)) / m
Diffraction and interference
By nuclear reactions, including the Sun’s nuclear fusion reactions, radioactive decay of certain elements, and atomic explosions (nuclear fission).
In waves with higher frequencies, photons have more energy.
The normal line is a line perpendicular to the surface at the point of incidence.
It behaves as only a wave can.
Wave theory.
The magnetic field (B) oscillates on the z-axis.
Yes, matter is also capable of exhibiting properties of both waves and particles.
It demonstrates the wave nature of light through the formation of interference fringes.
The superposition of secondary wavelets that generate from various parts of the wave front.
The order of the interference is denoted by m.
570 - 590 nm.
400 - 484 THz.
Interference is the act of superposition of two or more light waves emitted by two coherent sources travelling in the same medium.
Both diffraction and interference are behaviors of light waves that result in spatial patterns and depend on the wavelength.
No, infrared waves are invisible to the human eye with frequencies slightly lower than visible red light.
3.0 × 10^8 m/s
Total internal reflection occurs and the light ray cannot enter medium 2.
Yes, diffraction can happen with light from just one source.
Diffraction is used in tools for splitting light into a spectrum, like in CDs or DVDs.
Wave-particle duality is the concept that light and other forms of electromagnetic radiation exhibit both wave-like and particle-like properties.
Because each wavelength of sunlight forms its own pattern.
Particles unblocked by the barrier will continue in a straight line and shadows will be cast.
Diffraction is the bending of light waves around obstacles and openings. Interference is the phenomenon where two or more light waves superpose to form a resultant wave of greater, lower, or the same amplitude.
To understand the double-slit interference pattern by considering how two waves travel from the slits to the screen.
How two waves travel from the slits to the screen.
Something small, such as the closely spaced slits used by Young.
Bright fringes (or bright spots) are observed.
They interfere constructively, resulting in a bright fringe.
Diffraction and interference.
Yes, it has been verified for compound particles like atoms and even molecules.
Depending upon the circumstances of the experiment.
Wave-particle duality, Young’s double-slit experiment, Electromagnetic spectrum, Laws of reflection and refraction, Diffraction and interference.
Reflection of light.
Every wave in the electromagnetic spectrum.
A photon resembles a particle but moves like a wave.
The incident ray, the reflected ray, and the normal to the mirror at the point of incidence all lie in the same plane.
The wave nature of light.
The angle of incidence is equal to the angle of reflection (θi = θr).
When the incident ray is increased beyond the critical angle, causing the light to be reflected inside the medium instead of being refracted.
140,000 miles per second.
The electric field (E) oscillates on the y-axis.
The refractive index of medium 2.
A photon.
In small objects.
The Italian scientist Francesco Maria Grimaldi.
It spreads out.
526 - 606 THz.
Because some energy is dissipated when a wave is diffracted.
The size of the gap affects how much the waves spread out; smaller gaps cause more spreading.
The wave theory proposes that light travels in waves like an ocean wave or oscillating sound compressions.
The particle theory proposes that light comes in little packets or individual particles which are too small to see or distinguish.
When two waves combine to form a resultant wave with greater amplitude.
If light is a particle, only two slits will appear on the screen. If light is a wave, it will diffract and interfere, creating many fringes.
The light will diffract and interfere, making many fringes.
It indicates that light consists of waves, as the distribution of brightness can be explained by the alternately additive and subtractive interference of wavefronts.
Destructive interference occurs.
The light waves have random phase relationships.
A dark fringe appears on the screen.
Christian Huygens supports the wave theory.
Back and forth vibrations produce an alternating current.
Infrared waves are invisible to the human eye with frequencies slightly lower than visible red light.
As the ratio of the speed of light in a vacuum to the speed of light in the considered medium.
Most of the light is sent back into the same medium.
Young’s double-slit experiment
X-rays can cause cell mutations and/or cancer.
8.975°
The photos revealed tiny pinpoints of light passing through the double slits, suggesting that light consists of particles.
1.33
A rough and dull surface.
Snell's law.
Electromagnetic waves consist of waves of the electromagnetic field, which propagate through space and carry momentum and electromagnetic radiant energy.
Third-order constructive interference
The direction of travel (propagation) is on the x-axis.
X-ray.
It behaves as only particles can.
Infrared (IR) light.
Diffraction is the spreading out of waves when they pass an obstruction.
Diffraction occurs due to the superposition of secondary wavelets from various parts of the wave front, while interference is the result of the superposition of light waves from two coherent sources.
The superposition of light waves from two coherent sources.
A screen with two slits cut into it.
The wave edge bends at entry and exit.
Wave-particle duality.
It is diffracted into semicircular waves.
Electrons vibrating in an antenna.
Electronic circuitry.
Light is a form of energy which helps us to see objects.
Airport baggage screening, bone density scans, astronomy, archaeology, and inspection of manufactured goods.
The refractive index of a vacuum is 1.
Young’s double-slit experiment.
The refractive index indicates how much the speed of light is reduced in a medium compared to its speed in a vacuum.
Laws of reflection and refraction
No, the amount of energy in a photon depends on the frequency of the electromagnetic wave.
Light can be described by electromagnetic waves, which are transverse waves composed of two oscillating wave fields that vibrate perpendicular to each other.
520.0 nm
He observed a series of bright fringes on the screen.
Light can function as both a particle and a wave, depending on how the experiment is conducted and when observations are made.
The closer the slits are, the more is the spreading of the bright fringes.
The refractive index of medium 1.
An integral multiple of the wavelength, i.e., d sin θ = mλ, where m = 0, ±1, ±2, ...
θi is the angle of incidence and θr is the angle of refraction.
They are inversely proportional; as wavelength increases, frequency decreases.
Visible light represents only a small portion of the entire electromagnetic spectrum.
495 - 570 nm.
620 - 750 nm.
The effect of diffraction gradually gets less pronounced.
The superposition principle, which states that when two waves meet, the new wave they create is the sum of the two original waves.
The amplitude of the resultant wave will be twice the amplitude of the waves that are superposed.
The laws of reflection.
1.07
The size of the gap or obstacle should be close to the light's wavelength.
Light refracts away from the normal.
When light strikes a rough and dull surface, it bounces back in all directions giving rise to general illumination.
Ultraviolet light damages living cells.
The angle at which the refracted ray follows a path exactly along the surface of the dense medium.
A moving charge (i.e., electron).
The frequency of a wave is the number of waves that pass a fixed point in a given amount of time, such as the number of waves per second.
A changing magnetic field.
The angle θ between the path and a line from the slits to the screen is nearly the same for each path.
Everywhere, including outer space, Earth's atmosphere, and even moving through buildings and bodies.
Δl = d sin θ, where d is the distance between the slits and θ is the angle.
Light can behave as both a wave and a particle.
1 mile = 1.609344 km.
Electric devices, microwave ovens, TV signals, and medical imaging.
Diffraction.
Different wavelengths of electromagnetic waves produce different colors of visible light.
A series of bright and dark lines, known as interference fringes, are formed.
590 - 620 nm.
Any type of wave, including light, sound, and water waves.
They superpose each other.
Constructive interference occurs when two superposing waves are of the same amplitude and phase, resulting in a higher intensity of the resultant wave compared to the two separate waves.
The intensity of the resultant wave will be higher than the two separate waves.
The refractive index (n) is calculated by dividing the speed of light in a vacuum by the speed of light in the medium.
Interference makes patterns of bright and dark bands.
Diffraction makes a pattern with a central bright spot and other spots that get dimmer further out.
Single-slit experiments show how light spreads out.
Diffraction and interference.
No.
Ultraviolet light is necessary for humans to produce vitamin D.
Albert Einstein.
Formation of an image of the object.
Visible light.
Radio towers, power lines, radar, and radioactive materials.
Young's double-slit experiment.
d sin θ = (m + 1/2)λ, where m = 0, ±1, ±2, ...
380 - 450 nm.
The waves no longer spread out.
Radio wave has a higher frequency than ultraviolet wave.
Young's double-slit experiment.
1.0
Interference.
Interference needs light from sources that stay in step with each other.
Interference is used in things like holograms and measuring tiny distances.
It indicates that light exhibits wave-like properties.
n1 * sin(θi) = n2 * sin(θr).
Gamma ray.
The incident ray, the reflected ray, and the normal to the mirror at the point of incidence.
Gamma rays are used to sterilize food and medical equipment, and in radiation therapy to strategically target and kill cancerous tumor cells.
What we do with it and what we try to observe.
As a wave.
d sin θ = mλ, where m = 0, ±1, ±2, ...
λ is the wavelength of the light, d is the distance between the slits, and θ is the angle between the original direction of the beam.
450 - 495 nm.
The propagation direction and the amplitude.
The waves can curve around it.
The superposition gives the algebraic addition of the disturbances due to separate waves.
Wave-particle duality.
The electromagnetic spectrum.
Diffraction.
Destructive interference occurs when two superposing waves have the same amplitude but are of opposite phase, resulting in a resultant wave with lesser intensity than the two separate waves.
The wavelength of radio waves is longer than ultraviolet waves, thus the frequency of radio waves is lower than ultraviolet waves.
The patterns in both diffraction and interference depend a lot on the wavelength.
The laws of refraction.
n = (3.0 × 10^8 m/s) / (2.8 × 10^8 m/s)
The resultant intensity is lesser than the intensity of the two separate waves.
Electromagnetic waves consist of waves of the electromagnetic field.
1.5
n1 * sin(θi) = n2 * sin(θr)
Diffraction happens when a light wave bends around corners or through small openings. It is caused by light waves hitting an obstacle or passing through a small gap.
The path difference between waves should be a multiple of the wavelength.
The spacing in the pattern depends on the light's wavelength and the setup.
The spatial patterns from diffraction and interference are used in various applications in science and technology.
2.8 × 10^8 m/s
Interference happens when two light waves meet and mix together. It is caused by two or more light waves coming together.
Young's double-slit experiment shows interference.
The size of the spread-out light pattern depends on the wavelength.
