How long will the sun shine for? (relativistic energy)

AI Thread Summary
The sun radiates approximately 4.0E26 J/s, leading to a mass loss of about 4.44E9 kg per second, calculated using the equation ΔE=Δmc². Given the sun's mass of 2.0E30 kg, it can sustain this energy output for roughly 4.5E20 seconds, which translates to about 1.42E13 years. This calculation confirms the longevity of the sun's energy production at its current rate. The approach and results appear to be accurate based on the provided equations. Overall, the discussion effectively addresses the sun's energy output and its implications for longevity.
ElijahRockers
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Homework Statement



The sun radiates about 4.0E26 J/s.

a) How much mass is released as radiation each second?

b) If the mass of the sun is 2.0E30 kg, how long can the sun survive if the energy release continues at its present rate?

Homework Equations



Not sure, but I think I'm supposed to use

ΔE=Δmc2

The Attempt at a Solution



a)

Δm = ΔE/c2
Δm = 4.0E26/c2 = 4.44E9 kg/s

b)

2.0E30 kg x (1 s / 4.44E9 kg) =

4.5E20 seconds or
1.42E13 years

Is this correct?
 
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Yep, I think that's right.
 

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