What Are the Energy Changes in Mobile Phones and Televisions?

AI Thread Summary
Mobile phones and televisions involve several energy transformations during their operation. In mobile phones, sound energy from a user's voice is converted into mechanical vibrations, which are then transformed into electrical signals and ultimately into electromagnetic radiation for transmission. Televisions similarly convert digital or analog data into electrical pulses, which are then broadcast as electromagnetic radiation to be received and displayed. The discussion touches on the importance of understanding these energy changes, including the roles of mechanical, electrical, and electromagnetic energy. Broadcasting also requires a carrier wave, which facilitates the transmission of the signal.
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i was being ask to describe the energy changes involved in the use of mobile phones and a television

i m noot even sure i have fully understand the question,

energy change? say in mobile phone, all i can think of is signal wave turns to electric pulse which then changes into digital data... but it seem rather to staright forward so is there any other changes/?/

any energy invloves chemical or kinetic or potential ?

thanks
 
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Well for example in the case of a phone : let us say that A talkes to B over the phone.

When A talkes, his vocal cords make the air-molecules vibrate : that is how sound is generated. So the energy from the soundwave (which is a pressure wave) needs to be converted into an electrical signal. This is done by making a little plate vibrate (inside the phone), each vibration is converted into an electrical signal using for example a little wire that moves in a fixed magnetic field (due to Maxwell's laws they will generate a current in a wire that moves)... So now, the pressurewave (translational and vibrational energy) is converted into mechanical energy and then in electrical energy. Then you phone-operator will convert this electrical signal into EM-radiation (again a wave) that goes to the receiver of the phone of B. Then the reverse process starts : EM-wave to electrical signal to mechnical signal to pressure wave that will make B hear your message

marlon
 
umm interesting so for tv the digtal or anologo data from source (e.g tape, cd dvd ) is converted into eletric pulese , then our tv broadcast station converted electric plues into em-radiation then goes to reciever...and the goes

(skiped the Cathode Ray Tube part which produce the image for standard tv, i don't think i ve done cathode ray yet)

and i remmber in the process of broadcasting it requires a carrier, could anyone explain how exact this works? thx
 
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