Consider a cell phone that emits electromagnetic radiation with a frequency of 1.0 GHz and with a power of 100 W. (a) What is the electric field amplitude at a distance 1000 m away from the phone? Assume it radiates as a point source. Submit Answer Tries 0/8 (b) If your ear is only about 10 cm from the source of radiation, what is the electric field amplitude at your ear as you use the phone? Again assume the phone radiates as a point source. Submit Answer Tries 0/8 (c) If the phone can be turned on and stays transmitting for 2 h before discharging the battery, how much energy can be stored in the battery? Submit Answer Tries 0/8

Consider a cell phone that emits electromagnetic radiation with a frequency of 1.0 GHz and with a power of 100 W. (a) What is the electric field amplitude at a distance 1000 m away from the phone? Assume it radiates as a point source. Submit Answer Tries 0/8 (b) If your ear is only about 10 cm from the source of radiation, what is the electric field amplitude at your ear as you use the phone? Again assume the phone radiates as a point source. Submit Answer Tries 0/8 (c) If the phone can be turned on and stays transmitting for 2 h before discharging the battery, how much energy can be stored in the battery? Submit Answer Tries 0/8

University Physics Volume 2

18th Edition

ISBN:9781938168161

Author:OpenStax

Publisher:OpenStax

Chapter16: Electromagnetic Waves

Section: Chapter Questions

Problem 46P: A plane electromagnetic wave of frequency 20 GHz moves in the positive y-axis direction such that...

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