A blackboard with the sum E=mc2 written on it in white chalk.

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Images of chalk words on a blackboard.

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Size: 4256px × 2831px
Location: London, Ontario, Canada.
Photo credit: © Jonny White / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: =mc2, blackboard, chalk, einstein, einsteinian, energy, equation, equivalence, mass, mass–energy, maths, speed, squared, sum, velocity, word, written