Problem 8 TV Remote & SoundA remote contraol output a signal with power Po. (a) If the remote transmits the signal in all directionsequally, what is the intensity at a distance d from the remote control? (b) Now suppose the remoteinstead transmits the signal as a beam with an opening angle of 20. What is the intensity at the samedistance d in this case? (Think of this as a cone, treat the end at a distance d as a flat circle/disk.) (c)What is the ratio of the intensities?(d) Suppose you are standing a distance d away from a speaker and then walk towards the speaker so thatyou are only a distance of d/2 from the speaker. During your walk somebody increased the power outputof the speaker. You notice that the speaker now sounds twice as loud. How much did the power outputincrease by? (NOTE: something with a perceived increase in sound by two corresponds to a ten-foldincrease in intensity.)

(a). If the remote transmits the signal with power P0 in all directions equally, the intensity I1 at…

Problem 8 TV Remote & Sound A remote contraol output a signal with power Po. (a) If the remote transmits the signal in all directions equally, what is the intensity at a distance d from the remote control? (b) Now suppose the remote instead transmits the signal as a beam with an opening angle of 20. What is the intensity at the same distance d in this case? (Think of this as a cone, treat the end at a distance d as a flat circle/disk.) (c) What is the ratio of the intensities?

Problem 8 TV Remote & Sound A remote contraol output a signal with power Po. (a) If the remote transmits the signal in all directions equally, what is the intensity at a distance d from the remote control? (b) Now suppose the remote instead transmits the signal as a beam with an opening angle of 20. What is the intensity at the same distance d in this case? (Think of this as a cone, treat the end at a distance d as a flat circle/disk.) (c) What is the ratio of the intensities?

University Physics Volume 2

18th Edition

ISBN:9781938168161

Author:OpenStax

Publisher:OpenStax

Chapter16: Electromagnetic Waves

Section: Chapter Questions

Problem 93AP: On its highest power setting, a microwave oven increases the temperature of 0.400 kg of spaghetti by...

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