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Thread: A Probability Question

  1. #1 A Probability Question 
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    The following voltage waveform is to be sampled at a random time τ over a period of .
    a)What is the probability of that the sampled value v(t) <-0,5
    b)What is the probability of that the sampled value v(t)>1.25
    c)What is the probability of that the sampled value v(t)=1,25
    d)What is the probability of that the sampled value v(t)= -0,5


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  3. #2  
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    c) 0.1, d) 0.3. I'll leave the others for you.


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  4. #3  
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    d) must be 0
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  5. #4  
    mvb
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    In practice, the probabilities depend on the accuracy of the measurement of v during the sampling process. If you don't take this into account, I wouldn't be surprised if you could construct some anomalies, since the probability of finding any one point on a sloping straight line will be 0, and the probability of finding a position somewhere along the line will be greater than zero.
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    yes it is true. But I wonder while solving this problem is, what process do we use?
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  7. #6  
    mvb
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    Quote Originally Posted by mecnun9 View Post
    yes it is true. But I wonder while solving this problem is, what process do we use?
    The conceptually simplest way is to get the probability of getting a value between v- /2 and v + /2, and at the end of your calculation take the limit as goes to zero. Then to cover a region with measurements at a "point at a time," the points will be a distance apart. With care, you will get no anomalies. In real life, you could take to be the measurement error in your instrument and sum rather than integrate.
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    Quote Originally Posted by mecnun9 View Post
    d) must be 0
    You're right - I misread the picture. Somehow I saw it constant for an interval.
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