Question

According to Einstein’s formula, E=mc^2, the energy radiated away from the Sun (or any star for that matter) represents a loss in mass. That is, every Joule of energy radiated away from the Sun diminishes its mass by m=E/c^2.  Assume that the Sun’s luminosity is 3.8X10^26 J/s.

a) Determine the amount of mass (in kg) that the Sun would lose by shining at that same luminosity for 10 billion years.

b) Sirius A will last about 90 million years as a star that burns hydrogen into helium at a rate of 215 solar luminosity. Determine how much mass (in kg) Sirius A will lose over its lifetime.

Answer 1

니니 НА 27 ㄐㄐ 2 7 3x10