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Interacting with nature by K:

How to Offer Wild Birds Shelter in the Winter

Not all birds migrate south for the winter.  Winter is a hard season for birds, and many risk freezing to death at night. It doesn't take much effort or money to provide shelter for them, and it can make a huge difference to the little feathered guys!

More Articles >>

Calculation:  lightning's radiant heat energy relative to the Sun

We calculate lightning's heat energy relative to the Sun's as follows:

The energy radiated by a hot object per second is proportional to the fourth power of the absolute temperature and is expressed by this equation:

P = e σ A T4

where e is the emissivity of the object (e = 1 for ideal radiator), σ = 5.6703 x 10-8 watt/m2 and A is the surface area of the radiating body.

Thus, for each second, the ratio of the energy radiated by the Sun (Ps) to that radiated by lightning is (Pl) is given by

Ps / Pl = 10-4 As / As

assuming that the lightning temperature is 10 times the Sun's temperature and that both are ideal radiators.

The Sun's surface area is 0.609 x 1019 m2.

The surface area of a typical lightning bolt is 314 m2, assuming a bolt length of 100 m and a diameter of 2 m. 

Thus Ps / Pl = 7.66 x 1016 ~ 1017

Only one billionth of the Sun's radiant energy reaches Earth.  So the Sun's radiant energy that reaches Earth is 108  times a lightning's bolt radiant energy per unit second.

   

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