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fishboy39
Sep6-04, 07:25 PM
I have a physics problem that I am stuck on: Approximately 4 x 10^9 kg of matter is converted into energy each second in the sun. Find the power output of the sun. I know the answer is 3.6 x 10^26 W I just can't figure out how to get the correct equation and numbers. Any help would be appreciated. Thanks

Tide
Sep6-04, 07:29 PM
The relevant equation is
E = mc^2

geometer
Sep6-04, 07:35 PM
I have a physics problem that I am stuck on: Approximately 4 x 10^9 kg of matter is converted into energy each second in the sun. Find the power output of the sun. I know the answer is 3.6 x 10^26 W I just can't figure out how to get the correct equation and numbers. Any help would be appreciated. Thanks

Use [ tex ] E = mc^2 [ /tex] to convert the mass to energy, then power is just energy per unit time.

fishboy39
Sep6-04, 07:35 PM
Thanks! I knew it was something easy!

daveed
Sep6-04, 07:36 PM
...why not e=mc^2?

daveed
Sep6-04, 07:37 PM
LOL sorry must've left the window on too long... haha

Leong
Sep6-04, 07:38 PM
e=mc^2
P=\frac{\Delta e}{\Delta t}=\frac{\Delta mc^2}{\Delta t}
Given \frac{\Delta m}{\Delta t}= 4*10^9 kg/s
c=3.00*10^8 m/s

Galileo
Sep7-04, 04:17 AM
This reminds me of a lecture my (lively) optics professor gave.
He asked us to just imagine four billion kilograms of matter being
converted every second. :surprised
"Suppose you would throw 700 g brick up into outer space every second. (he freely demonstrates what it would be like).
Now imagine all the people in the world doing that." It's amazing :bugeye: