University Physics Volume 2

# Key Equations

### Key Equations

 AC voltage $v=V0sinωtv=V0sinωt$ AC current $i=I0sinωti=I0sinωt$ capacitive reactance $V0I0=1ωC=XCV0I0=1ωC=XC$ rms voltage $Vrms=V02Vrms=V02$ rms current $Irms=I02Irms=I02$ inductive reactance $V0I0=ωL=XLV0I0=ωL=XL$ Phase angle of an RLC series circuit $ϕ=tan−1XL−XCRϕ=tan−1XL−XCR$ AC version of Ohm’s law $I0=V0ZI0=V0Z$ Impedance of an RLC series circuit $Z=R2+(XL−XC)2Z=R2+(XL−XC)2$ Average power associated with a circuit element $Pave=12I0V0cosϕPave=12I0V0cosϕ$ Average power dissipated by a resistor $Pave=12I0V0=IrmsVrms=Irms2RPave=12I0V0=IrmsVrms=Irms2R$ Resonant angular frequency of a circuit $ω0=1LCω0=1LC$ Quality factor of a circuit $Q=ω0ΔωQ=ω0Δω$ Quality factor of a circuit in terms of the circuit parameters $Q=ω0LRQ=ω0LR$ Transformer equation with voltage $VSVP=NSNPVSVP=NSNP$ Transformer equation with current $IS=NPNSIPIS=NPNSIP$