U of O Physics Problems

In his short story "A Slight Case of Sunstroke", Arthur C. Clarke writes of a stadium full of disgruntled soccer fans barbecueing the dishonest referee by reflecting sunlight on him with mirrors found under their seats.

a.
Imagine a stadium at the equator at noon (i.e. the sun's directly overhead), with 50,000 fans (about the capacity of Autzen Stadium). Assuming that sunlight delivers about 1000 watts per square meter to the surface of the Earth, and that each fan is holding a mirror at , how much power would be available to be projected onto a dishonest referee?
b.
To be humane, lets replace the referee with a 50 kg cylinder of water. Assuming this cylinder absorbs all of the reflected light from the mirror - wielding fans, how long will it take for it to reach ? (The heat capacity of water is about 4200 )





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