Foucault experiment
E752312
The Foucault experiment is a 19th-century optical test devised by Léon Foucault to measure the speed of light with high precision using a rotating mirror apparatus.
All labels observed (2)
| Label | Occurrences |
|---|---|
| Foucault experiment canonical | 1 |
| Foucault rotating mirror experiment | 1 |
Statements (47)
| Predicate | Object |
|---|---|
| instanceOf |
optical experiment
ⓘ
physics experiment ⓘ speed of light measurement method ⓘ |
| appliesTo | finite speed of light ⓘ |
| basedOn |
angular deflection of reflected light
ⓘ
time-of-flight measurement ⓘ |
| comparedWith | Fizeau experiment NERFINISHED ⓘ |
| computes | speed of light from time delay inferred from angular deflection ⓘ |
| contradicts | emission theory prediction that light is faster in denser media ⓘ |
| countryOfOrigin | France ⓘ |
| describedIn | Léon Foucault’s publications on the speed of light ⓘ |
| field |
experimental physics
ⓘ
optics ⓘ |
| follows | Fizeau experiment NERFINISHED ⓘ |
| goal |
measure speed of light in air
ⓘ
measure speed of light in different media ⓘ |
| hasEffect | provided more accurate value of speed of light than previous methods ⓘ |
| hasPart |
collimating optics
ⓘ
fixed distant mirror ⓘ observation microscope or telescope ⓘ rapidly rotating mirror ⓘ |
| historicalPeriod | 19th-century physics ⓘ |
| inception |
19th century
ⓘ
circa 1850 ⓘ |
| influenced |
design of modern time-of-flight optical setups
ⓘ
later laboratory measurements of the speed of light ⓘ |
| inventor | Léon Foucault NERFINISHED ⓘ |
| mainSubject | speed of light ⓘ |
| measures |
difference between speed of light in air and water
ⓘ
speed of light in air ⓘ speed of light in water ⓘ |
| method | measure displacement of returning light spot due to mirror rotation ⓘ |
| namedAfter | Léon Foucault NERFINISHED ⓘ |
| notableFor |
high-precision measurement of the speed of light
ⓘ
improvement over astronomical methods of measuring light speed ⓘ |
| requires |
known angular velocity of rotating mirror
ⓘ
known distance between mirrors ⓘ |
| supportsTheory |
light travels slower in denser media
ⓘ
wave theory of light ⓘ |
| typeOf | laboratory measurement of fundamental constant ⓘ |
| usedFor |
historical demonstrations of speed of light measurement
ⓘ
teaching experimental methods in optics ⓘ |
| uses |
light beam
ⓘ
optical path with distant mirror ⓘ precision timing via angular deflection ⓘ rotating mirror ⓘ |
| verificationOf | finite and measurable speed of light ⓘ |
How these facts were elicited
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Instruction
You are a knowledge base construction expert. Given a subject entity and a description of it, return factual statements that you know for the subject as a JSON list of dictionaries(triples), where keys must be "subject", "predicate" and "object". The number of facts may be very high, between 25 to 50 or more, for very popular subjects. For less popular subjects, the number of facts can be very low, like 5 or 10. # Requirements - If you don't know the subject at all, return an empty list. - If the subject is not a named entity, return an empty list. - Include at least one triple where predicate is "instanceOf". - Do not get too wordy. - Separate several objects into multiple triples with one object.
Input
Subject: Foucault experiment Description of subject: The Foucault experiment is a 19th-century optical test devised by Léon Foucault to measure the speed of light with high precision using a rotating mirror apparatus.
Referenced by (2)
Full triples — surface form annotated when it differs from this entity's canonical label.
this entity surface form:
Foucault rotating mirror experiment