In the circuit shown in fig. potential diff. across L, C and and R are given. Find the e.m.f. of the source and calculate power factor of the circuit.

Explanation

Here, `V_(L) = 100 V, V_(R ) = 80 V`,
`V_(C ) = 40 V, V = ?`
`V = sqrt(V_(R )^(2) + (V_(L) - V_(C ))^(2)) = sqrt(80^(2) + (100 - 40)^(2))`
`=100 V`
Power factor, `cos phi = (V_(R ))/(V) = (80)/(100) = 0.8`