How to Calculate Decibels
- 1). Calculate power from ohms through the following formula: P=IR^2, where P=Power, I=Current and R=Resistance.
- 2). Define the bel as follows: Lb=log10 (P1/P0), where Lb=Bels and P1 and P0 are quantities.
- 3). Find the decibel, which is 0.1 bel, and can be expressed in the following formula: LdB=10log10 (P1/P0).
- 4). Express the decibel watt, which is the power of a signal in decibels relative to 1 watt and can be written as follows: dBW=10log10(W/1)=10log10(W), where dBW=Decibel Watts and W=Watts.
- 5). Combine these formulas into one conversion formula: dBW=10log10(W)=10log10(IR^2).
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