The Sun radiates 3.86x1026 W. Earth's distance from it is called an astronomical unit (AU) and...

 

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The Sun radiates 3.86x1026 W. Earth's distance from it is called an "astronomical unit" (AU) and that is roughly 1.50x10m. Earth itself has a radius of 6.37x10m. Use these numbers to calculate the temperature that Earth must have, in order that its radiated power equal the amount of power it absorbs from the Sun. Use = 5.67x10-8 (W/mK4) for the Stefan-Boltzmann constant. 1) Draw a pictorial representation of the problem. You may want to use separate pictures to represent the different stages of the problem outlined below. 2) Find the intensity of the Sun's light at Earth's location. 3) Treating the absorbing area of the Earth as a circle, find the total power absorbed by the Earth. 4) Treating the Earth as a spherical black body, and assuming the power that it emits is equal to the power absorbed from the Sun, find the temperature of the Earth. 5) Comment briefly on whether your result is reasonably believable. Look up the Earth's average surface temperature. What is the percent difference between your answer and this value? Is there a good reason you would expect your value to be higher or lower than the actual temperature? The Sun radiates 3.86x1026 W. Earth's distance from it is called an "astronomical unit" (AU) and that is roughly 1.50x10m. Earth itself has a radius of 6.37x10m. Use these numbers to calculate the temperature that Earth must have, in order that its radiated power equal the amount of power it absorbs from the Sun. Use = 5.67x10-8 (W/mK4) for the Stefan-Boltzmann constant. 1) Draw a pictorial representation of the problem. You may want to use separate pictures to represent the different stages of the problem outlined below. 2) Find the intensity of the Sun's light at Earth's location. 3) Treating the absorbing area of the Earth as a circle, find the total power absorbed by the Earth. 4) Treating the Earth as a spherical black body, and assuming the power that it emits is equal to the power absorbed from the Sun, find the temperature of the Earth. 5) Comment briefly on whether your result is reasonably believable. Look up the Earth's average surface temperature. What is the percent difference between your answer and this value? Is there a good reason you would expect your value to be higher or lower than the actual temperature?