Question

a capacitor of unknown value and an indicator of 0.1 H and resistor of 10 ohm are connected in series to a 220V, 50Hz ac source. It is found that the power factor of circuit is unity. Calculate the capacitance of capacitor and maximum amplitude of current..

Answer 1

From the given data:

L=0.1H

R=10$ohm$

Power factor i.e cos∅=1, cos∅=R/Z (Z=impedance)

therefore, 1=10/z

                z=10ΩΩ.

XL(inductive reactance= ωL

                                      =2πfL= 10π≈ 31.4Ω

Z=√R²+(XL-XC)²

sub. all the values

You will get Capacitance ∵ XC as 98.5mC

I= V/R

  =220/10

   =22A

Hope it was helpful

Regards

MANSHI