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Graduate How to calculate shadows in nanophotonics

  • qnach
  • · Replies 17 ·
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17

High School How small is the smallest hole that would still allow you to see through it?

  • xpell
  • · Replies 21 ·
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21

Graduate Photo-degradation of a biological sample

  • alemns
  • · Replies 4 ·
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4

Graduate Polarisation through a chiral nematic crystal

  • etotheipi
  • · Replies 9 ·
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9

Graduate Does a material change the direction of polarization of light?

  • Shadi Abdelhadi
  • · Replies 7 ·
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7

Graduate Can a two-stage light gas gun achieve 7 km/s with a 16 gram projectile?

  • Abdalrahman Azab
  • · Replies 1 ·
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1

Undergrad How do elliptical walls focus sound between the foci?

  • loreberto911
  • · Replies 2 ·
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2

Undergrad Why don't 180° out-of-phase waves create destructive interference in a string?

  • Vivek98phyboy
  • · Replies 3 ·
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3

Undergrad Differences between X-rays and Gamma rays

  • Rev. Cheeseman
  • · Replies 3 ·
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3

Undergrad Where does this formula for absorption cross section come from?

  • Haorong Wu
  • · Replies 1 ·
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1

High School What is the Definition of a Candela?

  • SamRoss
  • · Replies 10 ·
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10

Graduate Can you calculate optical density from permittivity and permeability?

  • Andrew Wright
  • · Replies 19 ·
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19

Undergrad Why does a divergent lens create an interference pattern?

  • qnt200
  • · Replies 3 ·
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3

Apparatus for a polarization filter rotator dial

  • tryingtolearn1
  • · Replies 6 ·
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6

High School Is the length of a light beam the number of crests times wavelength?

  • Speady
  • · Replies 13 ·
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13

Undergrad Waves and phase shifts (attempting to learn physics)

  • Nick tringali
  • · Replies 2 ·
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2

Graduate Why do laser beams from the same source interfere if independent beams don't?

  • danielhaish
  • · Replies 10 ·
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10

Undergrad Red-orange skies and wildfires

  • fog37
  • · Replies 1 ·
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1

High School Why can't light pass through to the dark side of a window?

  • danHa
  • · Replies 6 ·
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6

Graduate Kramers-Kronig relation for refractive index

  • Another
  • · Replies 1 ·
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1

High School The Physics of Color Perception

  • SecularSanity
  • · Replies 39 ·
2
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39

Undergrad Image in a glass sphere (Ray Optics)

  • anyonebutangel
  • · Replies 4 ·
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4

Graduate Does radar reflection differ between charged and uncharged objects?

  • faiello
  • · Replies 8 ·
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8

Graduate Fluid flow rate through pipes with changing diameter

  • notaphysicsmajor79
  • · Replies 1 ·
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1

High School Can we connect two laser sources to make a stronger beam with a larger radius?

  • danHa
  • · Replies 11 ·
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11

Undergrad Do two light waves with difference frequencies connect when they meet?

  • danielhaish
  • · Replies 5 ·
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5

High School Does the Torricelli Vacuum Experiment Prove the Strength of Vacuum Forces?

  • Rotating Wave
  • · Replies 39 ·
2
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39

Undergrad Measuring albedo with a digital camera and ImageJ histogram

  • brainpushups
  • · Replies 9 ·
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9

High School Light interacting with Matter -- Does the wavelength make a difference?

  • LightningInAJar
  • · Replies 13 ·
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13

Graduate Circular polarizing filter behavior with reflections and glare

  • Hornbein
  • · Replies 12 ·
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12

Undergrad Light speed and refractive index

  • avicenna
  • · Replies 25 ·
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25

Graduate Controlling output light power by constructive/destructive interference

  • Mayan Fung
  • · Replies 5 ·
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5

Undergrad What is the logic behind the mirror symmetry method of solving circuits?

  • Frigus
  • · Replies 18 ·
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18

High School Shadow of an object with light source at grazing incidence

  • xrayspecs
  • · Replies 7 ·
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7

High School Why do shadows change shape when light is shone on them?

  • danielhaish
  • · Replies 5 ·
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5

Graduate Why did Becquerel use black paper to test phosphorescence vs X-rays?

  • PainterGuy
  • · Replies 2 ·
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2

Graduate Maximum reception/transmission criteria for Conical Horn Antennas

  • tworitdash
  • · Replies 3 ·
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3

High School Can We Measure Diffraction Intensity Using Huygens' Principle?

  • jaumzaum
  • · Replies 4 ·
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4

Graduate Why do people refer to the "fast axis" vs. "slow axis" of Diode Lasers?

  • DaveE
  • · Replies 2 ·
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2

Graduate Concentric Meniscus Lenses Design

  • Ozen
  • · Replies 3 ·
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3

Undergrad Insight into polar coordinates (Newtonian mechanics)?

  • Leo Liu
  • · Replies 8 ·
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8

Graduate What Causes Molecules to Aggregate Over a Fiber in Optical Trapping?

  • Sciencestd
  • · Replies 2 ·
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2

Undergrad Why does light take a longer path in a rarer medium?

  • Fiona Rozario
  • · Replies 9 ·
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9

Graduate Why does the amount of Refraction depend on wavelength?

  • Fiona Rozario
  • · Replies 1 ·
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1

Graduate Modes of laser propagation in cylindrical optics

  • Sciencestd
  • · Replies 2 ·
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2

Graduate Transmission coefficient for nonuniform refractive index slab

  • {???}
  • · Replies 10 ·
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10

Undergrad Is the length of the arm r in a polar coordinate a function of the angle?

  • Leo Liu
  • · Replies 27 ·
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27

Graduate A particle moving with zero radial acceleration in polar coordinates

  • Leo Liu
  • · Replies 2 ·
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2

Undergrad My 50 year old Science book says that Black is the absence of all color

  • gary350
  • · Replies 22 ·
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22

Graduate Elliptical facet cylindrical optical fiber - Mathieu equation

  • Sciencestd
  • · Replies 1 ·
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1

Graduate Why does metal reflect light with a 180° phase shift classically?

  • jaumzaum
  • · Replies 4 ·
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4

Graduate Explaining TE₂₀ mode in rectangular waveguide using Feynman's reflection method

  • Dale12
  • · Replies 2 ·
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2

Undergrad Young's double slit experiment -- Question about this wavefront diagram

  • Sebas4
  • · Replies 4 ·
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4

Undergrad Focus or parallelize the light from an LED

  • Lexinas
  • · Replies 2 ·
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2

Undergrad Why subtract the glass angle from 90° for grazing exit into coating

  • GatoGordo
  • · Replies 4 ·
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4

Graduate Interference of light by splitting the wavefront and recombining

  • ItsKurious
  • · Replies 8 ·
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8

High School Are Polycarbonate Sunglasses Effective Against UV Rays?

  • Aeronautic Freek
  • · Replies 12 ·
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12

Graduate What are the key considerations for imaging with a condenser fresnel lens?

  • tud623
  • · Replies 58 ·
2
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58

Undergrad Why don't people hit the walls during curved flight in zero-G aircraft?

  • Aeronautic Freek
  • · Replies 11 ·
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11

Undergrad Geiger Counter and ultraviolet light sources

  • Lotic7
  • · Replies 18 ·
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18

Undergrad Y-component of the force vector in turning flight

  • Xorda
  • · Replies 10 ·
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10

Undergrad Can you make a more focused beam by using convex and concave lens?

  • physics-james
  • · Replies 1 ·
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1

Undergrad Affordable raytracing software under $1000

  • fsonnichsen
  • · Replies 2 ·
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2

Undergrad Thickness of dark wet spots on drying dishes

  • Orthoceras
  • · Replies 21 ·
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21

Graduate Some Flight Calculations and the Motion of the Earth

  • JohnMartin2009
  • · Replies 11 ·
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11

Undergrad Size of a light beam before and after Refraction

  • csirvi
  • · Replies 8 ·
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8

Graduate Photon wavelengths and frequencies

  • Quarinteen
  • · Replies 7 ·
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7

Undergrad How Should Light Be Illuminated in Spectrometer Designs for Liquid Analysis?

  • Getterdog
  • · Replies 12 ·
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12

Graduate Can anyone explain this derivation of the variable mass equation?

  • etotheipi
  • · Replies 4 ·
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4

Undergrad Does all light polarized parallel to the plane of incidence refract at Brewster's angle?

  • PainterGuy
  • · Replies 4 ·
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4

Undergrad Diffraction pattern from candle flame in front of TV screen

  • mike2020
  • · Replies 13 ·
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13

Undergrad Transmission and absorbance of materials in the deep UV

  • DariusP
  • · Replies 2 ·
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2

Undergrad What is the lifetime of a photon in a medium?

  • docnet
  • · Replies 3 ·
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3

Undergrad Optical wireless communication ideas

  • ElectroFractal
  • · Replies 10 ·
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10

Undergrad Effect of stacking diffraction gratings

  • mun
  • · Replies 9 ·
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9

High School Why does light slow down in a medium?

  • Jaffer2020
  • · Replies 41 ·
2
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41

High School How are spectral lines from different elements separated in observation?

  • roineust
  • · Replies 4 ·
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4

Undergrad Doppler effect and how it affects the light spectrum

  • roineust
  • · Replies 3 ·
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3

Graduate Trapping stiffness of optical tweezers

  • Sciencestd
  • · Replies 8 ·
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8

Graduate Does FTIR with a lens focus the evanescent wave or increase transmission?

  • mgkii
  • · Replies 6 ·
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6

High School Order of a dark fringe in Young's double slit experiment

  • FranzDiCoccio
  • · Replies 4 ·
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4

Graduate Polarization of elliptical fiber modes

  • Sciencestd
  • · Replies 2 ·
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2

Undergrad What is the meaning of polarization ratio?

  • Cheesycheese213
  • · Replies 1 ·
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1

Graduate Rearranging the equation for the cutoff condition in optical fibers

  • EmilyRuck
  • · Replies 2 ·
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2

Undergrad How does reflected light determine particle size in particle counters?

  • JoJoQuinoa
  • · Replies 3 ·
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3

Graduate Why does the evanescent field decay faster when cladding is replaced with air?

  • Sciencestd
  • · Replies 4 ·
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4

Undergrad How to find the length of a vector expressed in polar coordinates?

  • Tony Hau
  • · Replies 15 ·
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15

Graduate Polarization and intensity of a Gaussian beam

  • Sciencestd
  • · Replies 4 ·
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4

Undergrad Real Fresnel diffraction experiment

  • kent davidge
  • · Replies 1 ·
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1

Undergrad Why is the edge of the light from my flashlight beam so blurry?

  • somega
  • · Replies 1 ·
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1

Graduate Wide-angle X-ray scattering (WAXS) spectroscopy

  • anupama sharma
  • · Replies 1 ·
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1

Undergrad Are Fresnel and Fraunhofer diffraction the only tractable types?

  • kent davidge
  • · Replies 13 ·
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13

High School Does ripple frequency affect refraction angle and wave speed?

  • Volcano
  • · Replies 16 ·
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16

Graduate Evanescent field on optical waveguide with immersion medium of higher refractive index

  • Sciencestd
  • · Replies 14 ·
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14

Graduate Huygens Principle - how to explain this with classical language?

  • filip97
  • · Replies 2 ·
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2

High School Glass in flatbed scanner transparent to UV-C (~254nm)?

  • Speedloaf
  • · Replies 2 ·
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2

Undergrad Do stick edges appear to move at the same rate as center when rotating behind a lens?

  • roineust
  • · Replies 17 ·
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17

Undergrad Is the diffraction grating formula wrong?

  • ChrisXenon
  • · Replies 18 ·
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18

Undergrad Ray Diagram for an Experimental Lens Systems

  • Ozen
  • · Replies 17 ·
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17

Undergrad Photographing diffraction grating interference patterns

  • ChrisXenon
  • · Replies 17 ·
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17