A capacitor and a resistor are connected in series with an a.c. source. If the potential difference across C, R are 120 V and 90 V repectively, and if rms value of current is 3 A, calculate impedance and power factor of the circuit.

Explanation

Here, `V_(C ) = 120 V, V_(R ) = 90 V, I_(v) = 3 A`
`Z = ? Cos phi = ?`
`E_(v) = sqrt(V_(C )^(2) = V_(R )^(2)) = sqrt(120^(2) + 90^(2)) = 150 V`
`Z = (E_(v))/(I_(v)) = (150)/(3) = 50 ohm`
`cos phi = (R )/(Z) = (I_(v) xx R)/(I_(v) xx Z) = (V_(R ))/(E_(v)) = (90)/(150) = 0.6 `