An alternating voltage of `220` volts `r.m.s.` at a freqency of `40` cycles/sec is supplied to a circuit containing a pure inductance of `0.01 H` and

Monjur Alahi

An alternating voltage of `220` volts `r.m.s.` at a freqency of `40` cycles/sec is supplied to a circuit containing a pure inductance of `0.01 H` and a pure resistance of `6 ohms` in series.Calculate (i)the current , (ii)potential diffence across the resistance, (iii)potential difference across the inductance, (iv)the time lag, (v)power factor.


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Salim Ahmed Kawsar

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(i)`z=sqrt((omegaL)^(2)+R^(2))=sqrt((2pixx40xx0.01^(2))^(2)+6^(2))=sqrt((42.4))`
`I_(rms)=220/z=33.83 amp`
(ii)`V_(rms)=I_(rms)xxR=202.98` volts , (iii)`omegaLxxI_(rms)=96.83` volts
(iv)`t=T pi/(2pi)=0.01579 sec` , (v)`cos phi=R/Z=0.92`

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