2007-03-30 05:10:31 · 3 answers · asked by a a 1 in Science & Mathematics ➔ Engineering
RMS= 0.707*P-P
db= (20log10) (RMS )
2007-03-30 05:36:29 · answer #1 · answered by uisignorant 6 · 0⤊ 0⤋
The problem is there must be a reference in order to calculate dB. For instance, the ratio of the output of a low-pass filter to the input of the filter. The ratio of p-p output voltage to p-p input voltage is therefore dimensionless. Since it is a ratio, dB could be computed for a power ratio, a voltage ratio or a sound level ratio. There must be two same-dimension quantities where one is divided by the other.
If you mean dBV, then the reference voltage is 1 volt RMS. Your question refers to p-p volts, so you have to divide the conversion from p-p voltage to RMS by 2.
dBV = 20 log (base 10) (Vp-p *.707 / 2)
So, 2Vp-p is equal to -3.012 dBV
2007-03-30 05:44:51 · answer #2 · answered by zeb 4 · 0⤊ 0⤋
Vrms=1,414Vm=0,707Vpp
With the first formula you can calculate the rms value of your voltage.Then u can translate it to "db " with the following translation:
V(db)= (20log10) Vrms
2007-03-30 08:57:57 · answer #3 · answered by merkan222 1 · 0⤊ 0⤋