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Just what the title states

Some part or the other of this Globe faces approximately towards the Sun during each 24 hour period. What is the total amount of heat (in calories) incident on average during this 24-hour period?

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Does this answer your question: en.wikipedia.org/wiki/Earth%27s_energy_budget The values are in Watts, but just multiply by time (in seconds) to get heatin Joules and then convert to calories. –  Edu Jul 4 '12 at 20:31

1 Answer 1

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Ask Wolfram Alpha and Wikipedia

  • Surface area: $5.1 \times 10^{14} \text{ m}^2$
  • Radius: $6.4 \times 10^6\text{ m}$. Cross-sectional area = $\pi r^2 = 1.3 \times 10^{14}\text{ m}^2$
  • Solar constant $1360 \text{ W}/\text{m}^2$

So, multiply cross-section by power and divide by the surface area to get approximately 340 Watts average power at the cloud tops.

Conversion to calories is left as an exercise.

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