Question

The sun loses internal energy as it emits EM radiation at a rate of 3.8 x 1026 W. (a) How many kilograms of matter does the sun lose each second? (b) At this rate, how long would it take the sun to use up all its mass? (It’s current mass is 2.0*10^30kg.)

Answer 1

We know that

if we divide both sides by time, we can write it in terms of Power and Mass per unit time

or

So, putting the values, we get

Part b

Time to use all its mass

or