i was trying to verify the '8 years 7 months 6 days' myth/fact that states that you would have you scream for that much time to produce enough energy to warm up a cup of coffee. i assume that an average human screams at 80 dB.if i have to calculate the power,do i have to take the area of mouth opening into account?i think i do,but in the following article,the person who answered the question did not take it into account(or as it seems).
http://www.physicscentral.com/explore/poster-coffee.cfm
please answer.any help would be greatly appreciated.