In E=mc², what does c stand for?
AnswerThe speed of light
c is the speed of light in a vacuum, about 300,000 km per second.
Science · Facts & stats
Einstein facts & stats
7 fact-checked facts about Albert Einstein's life and physics, each with the reason behind it. 5 more are in today's round and join this page after it closes.
The basics
Einstein is most famous for which theory?
AnswerRelativity
His special and general theories of relativity reshaped physics.
Going deeper
Einstein's Nobel Prize in Physics was awarded mainly for explaining what?
AnswerThe photoelectric effect
The 1921 prize cited his discovery of the law of the photoelectric effect.
In what year did Einstein publish special relativity?
Answer1905
1905 was his 'miracle year', including the special relativity paper.
In what year did Einstein complete his general theory of relativity?
Answer1915
He presented the field equations of general relativity in late 1915.
Expert level
Who led the 1919 eclipse expedition that confirmed light bends near the Sun?
AnswerArthur Eddington
Eddington's eclipse measurements supported general relativity's prediction.
What is the atomic number of einsteinium, the element named after Einstein?
Answer99
Einsteinium, element 99, was first found in debris from a 1952 hydrogen bomb test.
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