Experiments Flashcards
demonstrated that light can behave as either a wave or a particle
Thomas Young’s double-slit experiment
contradicted the corpuscular theory of light
Thomas Young’s double-slit experiment
passing a beam of light through two narrowly spaced slits
Thomas Young’s double-slit experiment
more modern versions that add detectors showing which slit the light passes through
Thomas Young’s double-slit experiment
a modern variant, called a quantum eraser, demonstrates quantum entanglement
Thomas Young’s double-slit experiment
Claus Jönsson performed this experiment with electrons
Thomas Young’s double-slit experiment
can be performed with Mach–Zehnder interferometer with two half-silvered mirrors
Thomas Young’s double-slit experiment
Afshar experiment (variation showing principle of complementarity)
Thomas Young’s double-slit experiment
at Case Western Reserve University
Michelson-Morley experiment
disproved the existence of the luminiferous aether
Michelson-Morley experiment
mounted on a slab of stone floating in a pool of mercury so that it could turn without friction
Michelson-Morley experiment
Often called the most famous failed experiment in science
Michelson-Morley experiment
a fundamental test of special relativity
Michelson-Morley experiment
Dayton Miller tried to reproduce it on a large scale
Michelson-Morley experiment
Kennedy and Thorndike adapted it
Michelson-Morley experiment
a negative result can be explained by length contraction
Michelson-Morley experiment
Cavendish Laboratory at Cambridge
J. J. Thomson’s Cathode Ray Tubes
placed cathode ray tubes in an electric field and observed the deflection of the rays
J. J. Thomson’s Cathode Ray Tubes
measured using a fluorescent screen
J. J. Thomson’s Cathode Ray Tubes
discovered the electron
J. J. Thomson’s Cathode Ray Tubes
developed the “plum pudding” model of the atom
J. J. Thomson’s Cathode Ray Tubes
used modified Crookes tubes
J. J. Thomson’s Cathode Ray Tubes
Hans Geiger and Ernest Marsden
Rutherford gold foil experiment
discovered the positively charged nucleus of the atom
Rutherford gold foil experiment
it disproved J. J. Thomson’s plum pudding model
Rutherford gold foil experiment
fired alpha particles (helium nuclei) at a sheet of gold foil
Rutherford gold foil experiment
radium, radon, and bismuth-214 used to produce the alpha particles
Rutherford gold foil experiment
scattered particles were detected by a screen containing zinc sulfide
Rutherford gold foil experiment
produced scintillations
Rutherford gold foil experiment
led to the Geiger counter
Rutherford gold foil experiment
“It was almost as incredible as if you fired a 15-inch shell at a piece of tissue paper, and it came back and hit you.”
Rutherford gold foil experiment
demonstrated that the angular momentum of an atom is quantized
Stern-Gerlach experiment
A beam of silver atoms was fired through an inhomogeneous magnetic field
Stern-Gerlach experiment
sulfur from cigar smoke helped to visualize the spots on the detectors
Stern-Gerlach experiment
Phipps and Taylor performed a version using hydrogen
Stern-Gerlach experiment
Rabi oscillations critical to the development of MRI
Stern-Gerlach experiment
confirmed the de Broglie hypothesis by showing that electrons can exhibit wave-like behavior
Davisson-Germer experiment
confirmed wave-particle duality
Davisson-Germer experiment
a particle’s de Broglie wavelength is equal to Planck’s constant divided by its momentum
Davisson-Germer experiment
fired electrons at a nickel crystal and measured the diffraction patterns
Davisson-Germer experiment
used an electron counter called a Faraday box (or Faraday cup)
Davisson-Germer experiment
peak intensity was observed at 50 degrees and 54 electronvolts
Davisson-Germer experiment
diffraction is a property of waves, not particles, and thus could only be observed if electrons can act as waves
Davisson-Germer experiment
diffraction predicted for X-rays by Bragg’s law
Davisson-Germer experiment
pioneered the study of genetics
Gregor Mendel’s experiments with pea plants
was an Austrian monk
Gregor Mendel’s experiments with pea plants
law of segregation
Gregor Mendel’s experiments with pea plants
holds that each organism has two alleles for each trait
Gregor Mendel’s experiments with pea plants
law of independent assortment
Gregor Mendel’s experiments with pea plants
genes for individual traits are inherited independently
Gregor Mendel’s experiments with pea plants
worked with seven characteristics, including plant height, seed shape, and color
Gregor Mendel’s experiments with pea plants
Mendelian paradox (i.e. the data is too good to be true)
Gregor Mendel’s experiments with pea plants
sometimes called the “Waring Blender” experiment
Hershey-Chase experiment
demonstrated that the material responsible for the inheritance of traits was DNA rather than protein
Hershey-Chase experiment
carried out by creating radiolabeled T2 bacteriophages (viruses that infect bacteria)
Hershey-Chase experiment
phages’ DNA contained phosphorus-32 in its backbone or contained sulfur-35
Hershey-Chase experiment
phages allowed to infect E. coli
Hershey-Chase experiment
used a centrifuge to remove the viral coats from the bacteria called ‘ghosts’
Hershey-Chase experiment
viruses labeled with sulfur did not transfer their radioactivity to the cells, while the viruses labeled with phosphorus did
Hershey-Chase experiment
demonstrated that the genetic material was DNA, not protein
Hershey-Chase experiment
University of Chicago
Miller-Urey experiment
an attempt to demonstrate how life could form from inorganic chemicals
Miller-Urey experiment
modeled Earth’s prebiotic atmosphere as a mixture of water, methane (CH4), ammonia (NH3), and hydrogen
Miller-Urey experiment
allowed four substances to react in an apparatus over a one-week period
Miller-Urey experiment
included a heater to convert the water to water vapor and an electrode to simulate lightning strikes
Miller-Urey experiment
resulting mixture contained more than 20 distinct amino acids that formed spontaneously
Miller-Urey experiment
Joan Oró determined that hydrogen cyanide was critical in achieving results
Miller-Urey experiment
modern “volcanic” version of the experiment produced even more amino acids, including sulfur compounds
Miller-Urey experiment
proved that DNA replication is semiconservative
Meselson-Stahl experiment
used E. coli grown in a medium containing only nitrogen-15
Meselson-Stahl experiment
Columbia
Thomas Hunt Morgan’s fruit fly experiments
Fly Room
Thomas Hunt Morgan’s fruit fly experiments
room 613 of Schermerhorn Hall
Thomas Hunt Morgan’s fruit fly experiments
later at Caltech
Thomas Hunt Morgan’s fruit fly experiments
genetics experiments on the fruit fly (Drosophila melanogaster)
Thomas Hunt Morgan’s fruit fly experiments
genes are carried on chromosomes
Thomas Hunt Morgan’s fruit fly experiments
white-eyed mutant
Thomas Hunt Morgan’s fruit fly experiments
studies of mutations in the bread mold Neurospora (N. crassa)
Beadle and Tatum bread mold experiments
Neurospora could not thrive on a minimal medium, they needed to consume the twenty common amino acids
Beadle and Tatum bread mold experiments
new strains of Neurospora needed arginine to reproduce
Beadle and Tatum bread mold experiments
one gene-one enzyme hypothesis
Beadle and Tatum bread mold experiments
also did a famous experiment on maize
Beadle and Tatum bread mold experiments
measured the charge of the electron
Millikan Oil Drop
