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Help Strongly needed

  1. Sep 22, 2008 #1
    I want to know the relationship between Watts and Hertz in radio waves frequency?

    I have searched and searched for it and no satisfying results up till now. Anyway to be more clear consider that we have an RF generator which of course works with AC power we set it at 200 watts and it gives us for example 14 MHz of radio wave frequency.

    What I want to know is: Is there a certain rule between Watts and Hertz? And what is the relation between them? What will happen when increasing the wattage to ie.400 watts how can I calculate the Radio frequency Hertz produced?

    There's something I don't understand: when I asked an engineer about something like that he told me that if we use certain wattage (X) and it produced a certain Radio wave frequency in Hertz (Y) in some electrical appliance it wouldn't equal the hertz of the same wattage in another electrical appliance.

    This is really confusing for me as I am only 16 and I’m kinda new to the physics area.

    So kindly give me a response if you're 100 % sure of it and give me related topics in the “radio waves' frequency and its relation with Watts and electrical power” field that i can search and read about.
  2. jcsd
  3. Sep 22, 2008 #2


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    There is no direct relation at all between frequency (Hertz) and power (Watts), they are no more similar than e.g. length(meters) and weight(kg) or apples and oranges.
  4. Sep 23, 2008 #3


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    To elaborate; if you have a transmitter broadcasting at 14 MHz, and you're pumping 200 W through it, it will broadcast a 14 MHz signal at 200 W (well, a litle less, actually, but close to 200 W). If you increase the power to 400 W, it will still send a 14MHz signal, but the signal will be much stronger and have greater range. Yuo have incrased the amplitude of the radio wave you're broadcasting, but not the frequency. Of course, this is a radio transmitter, a device designed to hold at a certain frequency.

    Objects that simply emit radio waves when exited can emit many different frequencies at once. As input power changes, one or another of these frequencies may come into dominance. Just like a lightbulb emits white light (which is EM radiation) at full power, but can start to look yellow or brown during a partial power outage. The same bulb can actually start to turn blue and egt dim, if you put more power throught it, as it produces more of the higher-energy waves like blue, violet, and ultraviolet.

    There is, however, a relationship between frequency and energy, and this may be what you're looking for. You can read about it in Wikipedia, or this NASA site.
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