physicssun
posted by jen on .
a 1 square meter solar panel receives a total of 1000Watts from the sun. If we assume all the energy is release through nuclear fusion from the sun what is the total output from the sun?Given you know the total mass of the sun and have just calculated the total output assume the sun only consists of H and O in a proportion such that all of it can burn to make water, estimate how long the sun could burn at this rate til it runs out of H and O.

To get the total output of the sun, multiply your 1000 W/m^2 by the area of a sphere centered at the sun at Earth's distance, R. That area is 4 pi R^2. Now you will have the power emitted by the sun.
Next, look up the mass of the sun. Assume 1/9 of the mass is hydrogen abnd 8/9 of the mass in oxygen. These ae stoichiometric proportions. Calculate the chemical energy available if it all turns into H2O.
Divide that energy by the known energy release rate of the sun, from the first part. That will give you the time that the hydrogen and oxygen can last.