Hi guys, i have to learn from some papers this theory and im not sure i understand what`s going on with these meters and i want if you have some time to tell me if i solved correctly these problems.
1. With a DC voltmeter we want to measure the folowing signal: x(t)=4+3sin(w*t)+2sin(w*t)[V]
A DC voltmeter will see only the continue component( im not sure if it has this name in english, sorry if i confused you) of this signal so it will display the value: 4V.
2.Measure the following signal x(t)=2*sqrt(2)*sin(2wt)[V] with an AC voltmeter.
In my papers it says that the value displayed in this case is the peak voltage*0.707.
So, the value is 2V.
3. Here i have a problem. Again we use an AC voltmeter to measure a signal but in this case it has a continue part.
x(t)=3+2*sqrt(2)*sin(wt).
I dont know here if the peak voltage is (3+2*sqrt(2)) --- ( i think this is the right peak voltage) or 2*sqrt(2)).
All in all, i`d solve this exercise like this: U=(3+2*sqrt(2))*0.707=4.12V.
4.Calculate the mean voltage for the signal s(t)=2*sin^2(wt)
Mean voltage is the continue part ( if the signal doesnt have a continue part the mean voltage is 0) of the signal so sin^2(wt)=1/2(1-cos(wt))
s(t)=1-cos(wt).
The continue part is 1, so the mean voltage is 1V.
1. With a DC voltmeter we want to measure the folowing signal: x(t)=4+3sin(w*t)+2sin(w*t)[V]
A DC voltmeter will see only the continue component( im not sure if it has this name in english, sorry if i confused you) of this signal so it will display the value: 4V.
2.Measure the following signal x(t)=2*sqrt(2)*sin(2wt)[V] with an AC voltmeter.
In my papers it says that the value displayed in this case is the peak voltage*0.707.
So, the value is 2V.
3. Here i have a problem. Again we use an AC voltmeter to measure a signal but in this case it has a continue part.
x(t)=3+2*sqrt(2)*sin(wt).
I dont know here if the peak voltage is (3+2*sqrt(2)) --- ( i think this is the right peak voltage) or 2*sqrt(2)).
All in all, i`d solve this exercise like this: U=(3+2*sqrt(2))*0.707=4.12V.
4.Calculate the mean voltage for the signal s(t)=2*sin^2(wt)
Mean voltage is the continue part ( if the signal doesnt have a continue part the mean voltage is 0) of the signal so sin^2(wt)=1/2(1-cos(wt))
s(t)=1-cos(wt).
The continue part is 1, so the mean voltage is 1V.