In a hydrogen atom the electron is separated from the proton by an average distance of approximately 5.3*10^-11 m. Calculate the magnitude of the electrostatic force of attraction exerted by the proton on the electron.

Use Coulomb's law to determine the magnitude of the electrostatic force of attraction exerted by the proton on the electron. The magnitude of both the electron and proton charge is equal to the elementary charge e .
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