question_answer 12)

About 5% of the power of a 100 W lightbulb is converted to visible radiation. Whatis the average intensity of visible radiation? (a) at a distance of 1 m from the bulb? (b) at a distance of 10 m? Assume that the radiation is emitted is o tropically and neglect reflection.  

Answer:

(a) Visible power = 5 W Average intensity of radiation at 1 m (b) Average intensity of radiation at 10 m