Estimates show that the total energy output of a star is 2e26 J/s. What is the corresponding mass loss?

Answer 1

This is a perfect example of the use of Einsteins famous equation.

E = mc^2

2e26 J / 9e16 m^2/second^2 = m = 2.22e9 kg per second
(the 'per second' is added because the original *power* level was given -- not just a static energy number).

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