A coil of 0.01-henry inductance and 1-ohm resistance is connected to 200 volt, 50 Hz ac supply. Find the impedance of the circuit and time lag between max. alternating voltage and current.
R=1ω,L=0.01 H,V=200 V,v=50 Hz. Impedance of the circuit Z=R2+XL2=R2+(2πvL)2 =(1)2+(2×3.14×50×0.01)2 =1+9.86=10.86 =3.3Ω. ∴ For phase angle, tanϕ=Z/R tanϕ=RXL=R2πvL=12×3.14×50×0.01 tanϕ=3.14 ϕ=tan−13.14=72∘ Phase difference ϕ=180∘72×πrad ϕ=1.20 radian Time lag between alternating voltage and current ϕ=ωt t=ωϕ=180×2×π×5072×π=1501sec.
