The giant hornet Vespa mandarinia japonica preys on Japanese bees. However, if one of the hornets attempts to invade a beehive, several hundred of the bees quickly form a compact ball around the hornet to stop it. They don’t sting, bite, crush, or suffocate it. Rather they overheat it by quickly raising their body temperatures from the normal 35 C to 47 C or 48 C, which is lethal to the hornet but not to the bees . Assume the following: 500 bees form a ball of radius R=2.0 cm for a time t= 20 min, the primary loss of energy by the ball is by thermal radiation, the ball’s surface has emissivity ´=0.80, and the ball has a uniform temperature. On average, how much additional energy must each bee produce during the 20 min to maintain 47 C?

The giant hornet Vespa mandarinia japonica preys on Japanese bees. However, if one of the hornets attempts to invade a beehive, several hundred of the bees quickly form a compact ball around the hornet to stop it. They don’t sting, bite, crush, or suffocate it. Rather they overheat it by quickly raising their body temperatures from the normal 35 C to 47 C or 48 C, which is lethal to the hornet but not to the bees . Assume the following: 500 bees form a ball of radius R=2.0 cm for a time t= 20 min, the primary loss of energy by the ball is by thermal radiation, the ball’s surface has emissivity ´=0.80, and the ball has a uniform temperature. On average, how much additional energy must each bee produce during the 20 min to maintain 47 C?

Physics for Scientists and Engineers: Foundations and Connections

1st Edition

ISBN:9781133939146

Author:Katz, Debora M.

Publisher:Katz, Debora M.

Chapter21: Heat And The First Law Of Thermodynamics

Section: Chapter Questions

Problem 71PQ

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