Calculating Time to Heat Earth to 100°C

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The discussion revolves around calculating the time required for Earth to heat from 0°C to 100°C using the energy received from the Sun. The total energy intercepted is 1.27 x 10^17 W, and the Earth's volume is 1.08 x 10^21 m³, assumed to be entirely water. The participant outlines their approach using the formula Q=mc*deltaT, converting volume to mass and calculating the necessary energy for the temperature change. They arrive at an estimated time of approximately 113 years for the Earth to reach 100°C, confirming their calculations align with the equation provided. The focus remains on ensuring the accuracy of the calculations and the methodology used.
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Homework Statement


The Earth intercepts 1.27 x 10^17 W of radiant energy from the Sun. Suppose the Earth, of volume 1.08 x 10^21 m3, was composed of water. How long would it take for the Earth at 0°C to reach 100°C, if none of the energy was radiated or reflected back out into space?


Homework Equations


Q=mc*deltaT


The Attempt at a Solution


I just want to make sure that I did this correctly because the answer choices are all similar and vary by degrees of magnitude and I would like to avoid a simple mistake. Multiply the volume by 1000 to get the weight in kilograms, then multiply by 100, the temperature change. Multiply this by the specific heat. So:

1.27 x 10^17 = 1.08 x 10^24 kg * 4186 * 100

divide both sides by Q, gives a value in seconds. Convert to years which is approximately 113 years. Is this correct?
 
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your equation should be

(1.27 x 10^17)*t = 1.08 x 10^24 kg * 4186 * 100

But other than that, it looks like it should be correct.
 
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