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    Can you see the period of the wave for each of those time bases? The period is one complete cycle of the wave, so is 4cm for the displayed wave. Use the time base to convert that to seconds.

    Once you have the period of the wave in seconds, you can calculate its frequency. Frequency is defined as the number of cycles per second.

    If you have any issues, please post your working.
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    I don't understand
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    (Original post by 999sian)
    I don't understand
    Try this for a simple explanation:

    http://www.bbc.co.uk/schools/gcsebit...elecrev6.shtml
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    It's three different signals being plotted at three different timebases... which coincidentally have produced plots that all look the same (which allows the examiner to draw one diagram instead of three)

    so you've got to work out the first frequency (as shown in the posts above) then repeat for the other two. just pretend that you're looking at a fresh plot each time.
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    Still don't understand can someone tell me what to do ?
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    (Original post by 999sian)
    Still don't understand can someone tell me what to do ?
    The best thing you can do is to watch this excellent video.



    Follow it carefully and you will learn exactly what the basic measurements on an oscilloscope are and it will show you exactly how to solve this question and any others you are likely to encounter.

    Pay particular attention to:

    Amplitude
    Period
    Frequency

    and the relationship between the period and frequency. Make sure you learn what these are.
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    Yeah i get alll that but i still don't understand what the hell the question is asking. the video is don't explain anything useful. just tell me what to do
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    (Original post by 999sian)
    Yeah i get alll that but i still don't understand what the hell the question is asking. the video is don't explain anything useful. just tell me what to do
    It's asking for a frequency, the unit of frequency is Hz

    frequency is 1/period

    period is the amount of time between one peak and the next

    time is on the horizontal axis

    count the number of cm between 2 neighbouring peaks

    in part a there are 5ms per cm

    so what is the time between those neighbouring peaks? this is your period

    calculate 1/period

    write it down with the correct unit for frequency

    part a done.

    now repeat for the different amounts of time per cm as given in the question parts b and c
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    Holy **** someone actually explains something thank you very much. for part a i got 0.05Hz for the frequany. in part B and C the units are differnt so how do i convert it to the correct units
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    (Original post by 999sian)
    Holy **** someone actually explains something thank you very much. for part a i got 0.05Hz for the frequany. in part B and C the units are differnt so how do i convert it to the correct units
    0.05 Hz is not correct. Also, you learn nothing if we do your homework for you by telling you the answers (which is what you seem to be asking for)
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    What did i do wrong then. i don't understand
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    All wanted was an explanation like the person above said. don't just tell someone their wrong explain how to get the correct answer. i know it 50hz now because of unit conversions. My Physics teacher is complete **** and gives us work to do and does not bother to teach us it and expects us to just know it and if we go and ask for help he just tells us off.
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    (Original post by 999sian)
    All wanted was an explanation like the person above said. don't just tell someone their wrong explain how to get the correct answer. i know it 50hz now because of unit conversions. My Physics teacher is complete **** and gives us work to do and does not bother to teach us it and expects us to just know it and if we go and ask for help he just tells us off.
    So you've got it now for all 3 parts?
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    (Original post by 999sian)
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    Each Square is a cm. One whole cycle (or wavelength) has 4 squares.
    i) if one square unit is 5ms, one cycle takes 20ms (because 5msx4=20ms). Frequency(f) = no. of cycles/second. In this case it's 1 cycle per 20ms (convert to standard units. 1000ms=1second therefore, 20ms=0.02s) so f=1/0.02s=50Hz.

    Apply the same method to the following parts. Was that helpful in making you understand?? If you become clear with the basic concepts, you'll have no problem in applying the same principle to other questions.
 
 
 
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